//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. //===----------------------------------------------------------------------===/ // // This file implements semantic analysis for C++ templates. //===----------------------------------------------------------------------===/ #include "clang/Sema/SemaInternal.h" #include "clang/Sema/Lookup.h" #include "clang/Sema/Scope.h" #include "clang/Sema/Template.h" #include "clang/Sema/TemplateDeduction.h" #include "TreeTransform.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Expr.h" #include "clang/AST/ExprCXX.h" #include "clang/AST/DeclFriend.h" #include "clang/AST/DeclTemplate.h" #include "clang/Sema/DeclSpec.h" #include "clang/Sema/ParsedTemplate.h" #include "clang/Basic/LangOptions.h" #include "clang/Basic/PartialDiagnostic.h" #include "llvm/ADT/StringExtras.h" using namespace clang; using namespace sema; /// \brief Determine whether the declaration found is acceptable as the name /// of a template and, if so, return that template declaration. Otherwise, /// returns NULL. static NamedDecl *isAcceptableTemplateName(ASTContext &Context, NamedDecl *Orig) { NamedDecl *D = Orig->getUnderlyingDecl(); if (isa<TemplateDecl>(D)) return Orig; if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { // C++ [temp.local]p1: // Like normal (non-template) classes, class templates have an // injected-class-name (Clause 9). The injected-class-name // can be used with or without a template-argument-list. When // it is used without a template-argument-list, it is // equivalent to the injected-class-name followed by the // template-parameters of the class template enclosed in // <>. When it is used with a template-argument-list, it // refers to the specified class template specialization, // which could be the current specialization or another // specialization. if (Record->isInjectedClassName()) { Record = cast<CXXRecordDecl>(Record->getDeclContext()); if (Record->getDescribedClassTemplate()) return Record->getDescribedClassTemplate(); if (ClassTemplateSpecializationDecl *Spec = dyn_cast<ClassTemplateSpecializationDecl>(Record)) return Spec->getSpecializedTemplate(); } return 0; } return 0; } static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { // The set of class templates we've already seen. llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; LookupResult::Filter filter = R.makeFilter(); while (filter.hasNext()) { NamedDecl *Orig = filter.next(); NamedDecl *Repl = isAcceptableTemplateName(C, Orig); if (!Repl) filter.erase(); else if (Repl != Orig) { // C++ [temp.local]p3: // A lookup that finds an injected-class-name (10.2) can result in an // ambiguity in certain cases (for example, if it is found in more than // one base class). If all of the injected-class-names that are found // refer to specializations of the same class template, and if the name // is followed by a template-argument-list, the reference refers to the // class template itself and not a specialization thereof, and is not // ambiguous. // // FIXME: Will we eventually have to do the same for alias templates? if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) if (!ClassTemplates.insert(ClassTmpl)) { filter.erase(); continue; } // FIXME: we promote access to public here as a workaround to // the fact that LookupResult doesn't let us remember that we // found this template through a particular injected class name, // which means we end up doing nasty things to the invariants. // Pretending that access is public is *much* safer. filter.replace(Repl, AS_public); } } filter.done(); } TemplateNameKind Sema::isTemplateName(Scope *S, CXXScopeSpec &SS, bool hasTemplateKeyword, UnqualifiedId &Name, ParsedType ObjectTypePtr, bool EnteringContext, TemplateTy &TemplateResult, bool &MemberOfUnknownSpecialization) { assert(getLangOptions().CPlusPlus && "No template names in C!"); DeclarationName TName; MemberOfUnknownSpecialization = false; switch (Name.getKind()) { case UnqualifiedId::IK_Identifier: TName = DeclarationName(Name.Identifier); break; case UnqualifiedId::IK_OperatorFunctionId: TName = Context.DeclarationNames.getCXXOperatorName( Name.OperatorFunctionId.Operator); break; case UnqualifiedId::IK_LiteralOperatorId: TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); break; default: return TNK_Non_template; } QualType ObjectType = ObjectTypePtr.get(); LookupResult R(*this, TName, Name.getSourceRange().getBegin(), LookupOrdinaryName); LookupTemplateName(R, S, SS, ObjectType, EnteringContext, MemberOfUnknownSpecialization); if (R.empty()) return TNK_Non_template; if (R.isAmbiguous()) { // Suppress diagnostics; we'll redo this lookup later. R.suppressDiagnostics(); // FIXME: we might have ambiguous templates, in which case we // should at least parse them properly! return TNK_Non_template; } TemplateName Template; TemplateNameKind TemplateKind; unsigned ResultCount = R.end() - R.begin(); if (ResultCount > 1) { // We assume that we'll preserve the qualifier from a function // template name in other ways. Template = Context.getOverloadedTemplateName(R.begin(), R.end()); TemplateKind = TNK_Function_template; // We'll do this lookup again later. R.suppressDiagnostics(); } else { TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); if (SS.isSet() && !SS.isInvalid()) { NestedNameSpecifier *Qualifier = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); Template = Context.getQualifiedTemplateName(Qualifier, hasTemplateKeyword, TD); } else { Template = TemplateName(TD); } if (isa<FunctionTemplateDecl>(TD)) { TemplateKind = TNK_Function_template; // We'll do this lookup again later. R.suppressDiagnostics(); } else { assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); TemplateKind = TNK_Type_template; } } TemplateResult = TemplateTy::make(Template); return TemplateKind; } bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, SourceLocation IILoc, Scope *S, const CXXScopeSpec *SS, TemplateTy &SuggestedTemplate, TemplateNameKind &SuggestedKind) { // We can't recover unless there's a dependent scope specifier preceding the // template name. // FIXME: Typo correction? if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || computeDeclContext(*SS)) return false; // The code is missing a 'template' keyword prior to the dependent template // name. NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); Diag(IILoc, diag::err_template_kw_missing) << Qualifier << II.getName() << FixItHint::CreateInsertion(IILoc, "template "); SuggestedTemplate = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); SuggestedKind = TNK_Dependent_template_name; return true; } void Sema::LookupTemplateName(LookupResult &Found, Scope *S, CXXScopeSpec &SS, QualType ObjectType, bool EnteringContext, bool &MemberOfUnknownSpecialization) { // Determine where to perform name lookup MemberOfUnknownSpecialization = false; DeclContext *LookupCtx = 0; bool isDependent = false; if (!ObjectType.isNull()) { // This nested-name-specifier occurs in a member access expression, e.g., // x->B::f, and we are looking into the type of the object. assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); LookupCtx = computeDeclContext(ObjectType); isDependent = ObjectType->isDependentType(); assert((isDependent || !ObjectType->isIncompleteType()) && "Caller should have completed object type"); } else if (SS.isSet()) { // This nested-name-specifier occurs after another nested-name-specifier, // so long into the context associated with the prior nested-name-specifier. LookupCtx = computeDeclContext(SS, EnteringContext); isDependent = isDependentScopeSpecifier(SS); // The declaration context must be complete. if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) return; } bool ObjectTypeSearchedInScope = false; if (LookupCtx) { // Perform "qualified" name lookup into the declaration context we // computed, which is either the type of the base of a member access // expression or the declaration context associated with a prior // nested-name-specifier. LookupQualifiedName(Found, LookupCtx); if (!ObjectType.isNull() && Found.empty()) { // C++ [basic.lookup.classref]p1: // In a class member access expression (5.2.5), if the . or -> token is // immediately followed by an identifier followed by a <, the // identifier must be looked up to determine whether the < is the // beginning of a template argument list (14.2) or a less-than operator. // The identifier is first looked up in the class of the object // expression. If the identifier is not found, it is then looked up in // the context of the entire postfix-expression and shall name a class // or function template. if (S) LookupName(Found, S); ObjectTypeSearchedInScope = true; } } else if (isDependent && (!S || ObjectType.isNull())) { // We cannot look into a dependent object type or nested nme // specifier. MemberOfUnknownSpecialization = true; return; } else { // Perform unqualified name lookup in the current scope. LookupName(Found, S); } if (Found.empty() && !isDependent) { // If we did not find any names, attempt to correct any typos. DeclarationName Name = Found.getLookupName(); if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, false, CTC_CXXCasts)) { FilterAcceptableTemplateNames(Context, Found); if (!Found.empty()) { if (LookupCtx) Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) << Name << LookupCtx << Found.getLookupName() << SS.getRange() << FixItHint::CreateReplacement(Found.getNameLoc(), Found.getLookupName().getAsString()); else Diag(Found.getNameLoc(), diag::err_no_template_suggest) << Name << Found.getLookupName() << FixItHint::CreateReplacement(Found.getNameLoc(), Found.getLookupName().getAsString()); if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) Diag(Template->getLocation(), diag::note_previous_decl) << Template->getDeclName(); } } else { Found.clear(); Found.setLookupName(Name); } } FilterAcceptableTemplateNames(Context, Found); if (Found.empty()) { if (isDependent) MemberOfUnknownSpecialization = true; return; } if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { // C++ [basic.lookup.classref]p1: // [...] If the lookup in the class of the object expression finds a // template, the name is also looked up in the context of the entire // postfix-expression and [...] // LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), LookupOrdinaryName); LookupName(FoundOuter, S); FilterAcceptableTemplateNames(Context, FoundOuter); if (FoundOuter.empty()) { // - if the name is not found, the name found in the class of the // object expression is used, otherwise } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { // - if the name is found in the context of the entire // postfix-expression and does not name a class template, the name // found in the class of the object expression is used, otherwise } else if (!Found.isSuppressingDiagnostics()) { // - if the name found is a class template, it must refer to the same // entity as the one found in the class of the object expression, // otherwise the program is ill-formed. if (!Found.isSingleResult() || Found.getFoundDecl()->getCanonicalDecl() != FoundOuter.getFoundDecl()->getCanonicalDecl()) { Diag(Found.getNameLoc(), diag::ext_nested_name_member_ref_lookup_ambiguous) << Found.getLookupName() << ObjectType; Diag(Found.getRepresentativeDecl()->getLocation(), diag::note_ambig_member_ref_object_type) << ObjectType; Diag(FoundOuter.getFoundDecl()->getLocation(), diag::note_ambig_member_ref_scope); // Recover by taking the template that we found in the object // expression's type. } } } } /// ActOnDependentIdExpression - Handle a dependent id-expression that /// was just parsed. This is only possible with an explicit scope /// specifier naming a dependent type. ExprResult Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, bool isAddressOfOperand, const TemplateArgumentListInfo *TemplateArgs) { NestedNameSpecifier *Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); DeclContext *DC = getFunctionLevelDeclContext(); if (!isAddressOfOperand && isa<CXXMethodDecl>(DC) && cast<CXXMethodDecl>(DC)->isInstance()) { QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); // Since the 'this' expression is synthesized, we don't need to // perform the double-lookup check. NamedDecl *FirstQualifierInScope = 0; return Owned(CXXDependentScopeMemberExpr::Create(Context, /*This*/ 0, ThisType, /*IsArrow*/ true, /*Op*/ SourceLocation(), Qualifier, SS.getRange(), FirstQualifierInScope, NameInfo, TemplateArgs)); } return BuildDependentDeclRefExpr(SS, NameInfo, TemplateArgs); } ExprResult Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, const TemplateArgumentListInfo *TemplateArgs) { return Owned(DependentScopeDeclRefExpr::Create(Context, static_cast<NestedNameSpecifier*>(SS.getScopeRep()), SS.getRange(), NameInfo, TemplateArgs)); } /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining /// that the template parameter 'PrevDecl' is being shadowed by a new /// declaration at location Loc. Returns true to indicate that this is /// an error, and false otherwise. bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); // Microsoft Visual C++ permits template parameters to be shadowed. if (getLangOptions().Microsoft) return false; // C++ [temp.local]p4: // A template-parameter shall not be redeclared within its // scope (including nested scopes). Diag(Loc, diag::err_template_param_shadow) << cast<NamedDecl>(PrevDecl)->getDeclName(); Diag(PrevDecl->getLocation(), diag::note_template_param_here); return true; } /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset /// the parameter D to reference the templated declaration and return a pointer /// to the template declaration. Otherwise, do nothing to D and return null. TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) { if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) { D = Temp->getTemplatedDecl(); return Temp; } return 0; } static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, const ParsedTemplateArgument &Arg) { switch (Arg.getKind()) { case ParsedTemplateArgument::Type: { TypeSourceInfo *DI; QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); if (!DI) DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); return TemplateArgumentLoc(TemplateArgument(T), DI); } case ParsedTemplateArgument::NonType: { Expr *E = static_cast<Expr *>(Arg.getAsExpr()); return TemplateArgumentLoc(TemplateArgument(E), E); } case ParsedTemplateArgument::Template: { TemplateName Template = Arg.getAsTemplate().get(); return TemplateArgumentLoc(TemplateArgument(Template), Arg.getScopeSpec().getRange(), Arg.getLocation()); } } llvm_unreachable("Unhandled parsed template argument"); return TemplateArgumentLoc(); } /// \brief Translates template arguments as provided by the parser /// into template arguments used by semantic analysis. void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, TemplateArgumentListInfo &TemplateArgs) { for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) TemplateArgs.addArgument(translateTemplateArgument(*this, TemplateArgsIn[I])); } /// ActOnTypeParameter - Called when a C++ template type parameter /// (e.g., "typename T") has been parsed. Typename specifies whether /// the keyword "typename" was used to declare the type parameter /// (otherwise, "class" was used), and KeyLoc is the location of the /// "class" or "typename" keyword. ParamName is the name of the /// parameter (NULL indicates an unnamed template parameter) and /// ParamName is the location of the parameter name (if any). /// If the type parameter has a default argument, it will be added /// later via ActOnTypeParameterDefault. Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, SourceLocation EllipsisLoc, SourceLocation KeyLoc, IdentifierInfo *ParamName, SourceLocation ParamNameLoc, unsigned Depth, unsigned Position, SourceLocation EqualLoc, ParsedType DefaultArg) { assert(S->isTemplateParamScope() && "Template type parameter not in template parameter scope!"); bool Invalid = false; if (ParamName) { NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, LookupOrdinaryName, ForRedeclaration); if (PrevDecl && PrevDecl->isTemplateParameter()) Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, PrevDecl); } SourceLocation Loc = ParamNameLoc; if (!ParamName) Loc = KeyLoc; TemplateTypeParmDecl *Param = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), Loc, Depth, Position, ParamName, Typename, Ellipsis); if (Invalid) Param->setInvalidDecl(); if (ParamName) { // Add the template parameter into the current scope. S->AddDecl(Param); IdResolver.AddDecl(Param); } // Handle the default argument, if provided. if (DefaultArg) { TypeSourceInfo *DefaultTInfo; GetTypeFromParser(DefaultArg, &DefaultTInfo); assert(DefaultTInfo && "expected source information for type"); // C++0x [temp.param]p9: // A default template-argument may be specified for any kind of // template-parameter that is not a template parameter pack. if (Ellipsis) { Diag(EqualLoc, diag::err_template_param_pack_default_arg); return Param; } // Check the template argument itself. if (CheckTemplateArgument(Param, DefaultTInfo)) { Param->setInvalidDecl(); return Param; } Param->setDefaultArgument(DefaultTInfo, false); } return Param; } /// \brief Check that the type of a non-type template parameter is /// well-formed. /// /// \returns the (possibly-promoted) parameter type if valid; /// otherwise, produces a diagnostic and returns a NULL type. QualType Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { // We don't allow variably-modified types as the type of non-type template // parameters. if (T->isVariablyModifiedType()) { Diag(Loc, diag::err_variably_modified_nontype_template_param) << T; return QualType(); } // C++ [temp.param]p4: // // A non-type template-parameter shall have one of the following // (optionally cv-qualified) types: // // -- integral or enumeration type, if (T->isIntegralOrEnumerationType() || // -- pointer to object or pointer to function, T->isPointerType() || // -- reference to object or reference to function, T->isReferenceType() || // -- pointer to member. T->isMemberPointerType() || // If T is a dependent type, we can't do the check now, so we // assume that it is well-formed. T->isDependentType()) return T; // C++ [temp.param]p8: // // A non-type template-parameter of type "array of T" or // "function returning T" is adjusted to be of type "pointer to // T" or "pointer to function returning T", respectively. else if (T->isArrayType()) // FIXME: Keep the type prior to promotion? return Context.getArrayDecayedType(T); else if (T->isFunctionType()) // FIXME: Keep the type prior to promotion? return Context.getPointerType(T); Diag(Loc, diag::err_template_nontype_parm_bad_type) << T; return QualType(); } Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, unsigned Depth, unsigned Position, SourceLocation EqualLoc, Expr *Default) { TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType T = TInfo->getType(); assert(S->isTemplateParamScope() && "Non-type template parameter not in template parameter scope!"); bool Invalid = false; IdentifierInfo *ParamName = D.getIdentifier(); if (ParamName) { NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), LookupOrdinaryName, ForRedeclaration); if (PrevDecl && PrevDecl->isTemplateParameter()) Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); } T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); if (T.isNull()) { T = Context.IntTy; // Recover with an 'int' type. Invalid = true; } NonTypeTemplateParmDecl *Param = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), D.getIdentifierLoc(), Depth, Position, ParamName, T, TInfo); if (Invalid) Param->setInvalidDecl(); if (D.getIdentifier()) { // Add the template parameter into the current scope. S->AddDecl(Param); IdResolver.AddDecl(Param); } // Check the well-formedness of the default template argument, if provided. if (Default) { TemplateArgument Converted; if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) { Param->setInvalidDecl(); return Param; } Param->setDefaultArgument(Default, false); } return Param; } /// ActOnTemplateTemplateParameter - Called when a C++ template template /// parameter (e.g. T in template <template <typename> class T> class array) /// has been parsed. S is the current scope. Decl *Sema::ActOnTemplateTemplateParameter(Scope* S, SourceLocation TmpLoc, TemplateParamsTy *Params, IdentifierInfo *Name, SourceLocation NameLoc, unsigned Depth, unsigned Position, SourceLocation EqualLoc, const ParsedTemplateArgument &Default) { assert(S->isTemplateParamScope() && "Template template parameter not in template parameter scope!"); // Construct the parameter object. TemplateTemplateParmDecl *Param = TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), NameLoc.isInvalid()? TmpLoc : NameLoc, Depth, Position, Name, (TemplateParameterList*)Params); // If the template template parameter has a name, then link the identifier // into the scope and lookup mechanisms. if (Name) { S->AddDecl(Param); IdResolver.AddDecl(Param); } if (!Default.isInvalid()) { // Check only that we have a template template argument. We don't want to // try to check well-formedness now, because our template template parameter // might have dependent types in its template parameters, which we wouldn't // be able to match now. // // If none of the template template parameter's template arguments mention // other template parameters, we could actually perform more checking here. // However, it isn't worth doing. TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); if (DefaultArg.getArgument().getAsTemplate().isNull()) { Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) << DefaultArg.getSourceRange(); return Param; } Param->setDefaultArgument(DefaultArg, false); } return Param; } /// ActOnTemplateParameterList - Builds a TemplateParameterList that /// contains the template parameters in Params/NumParams. Sema::TemplateParamsTy * Sema::ActOnTemplateParameterList(unsigned Depth, SourceLocation ExportLoc, SourceLocation TemplateLoc, SourceLocation LAngleLoc, Decl **Params, unsigned NumParams, SourceLocation RAngleLoc) { if (ExportLoc.isValid()) Diag(ExportLoc, diag::warn_template_export_unsupported); return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, (NamedDecl**)Params, NumParams, RAngleLoc); } static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { if (SS.isSet()) T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), SS.getRange()); } DeclResult Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc, CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc, AttributeList *Attr, TemplateParameterList *TemplateParams, AccessSpecifier AS) { assert(TemplateParams && TemplateParams->size() > 0 && "No template parameters"); assert(TUK != TUK_Reference && "Can only declare or define class templates"); bool Invalid = false; // Check that we can declare a template here. if (CheckTemplateDeclScope(S, TemplateParams)) return true; TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); assert(Kind != TTK_Enum && "can't build template of enumerated type"); // There is no such thing as an unnamed class template. if (!Name) { Diag(KWLoc, diag::err_template_unnamed_class); return true; } // Find any previous declaration with this name. DeclContext *SemanticContext; LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, ForRedeclaration); if (SS.isNotEmpty() && !SS.isInvalid()) { SemanticContext = computeDeclContext(SS, true); if (!SemanticContext) { // FIXME: Produce a reasonable diagnostic here return true; } if (RequireCompleteDeclContext(SS, SemanticContext)) return true; LookupQualifiedName(Previous, SemanticContext); } else { SemanticContext = CurContext; LookupName(Previous, S); } if (Previous.isAmbiguous()) return true; NamedDecl *PrevDecl = 0; if (Previous.begin() != Previous.end()) PrevDecl = (*Previous.begin())->getUnderlyingDecl(); // If there is a previous declaration with the same name, check // whether this is a valid redeclaration. ClassTemplateDecl *PrevClassTemplate = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); // We may have found the injected-class-name of a class template, // class template partial specialization, or class template specialization. // In these cases, grab the template that is being defined or specialized. if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); PrevClassTemplate = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { PrevClassTemplate = cast<ClassTemplateSpecializationDecl>(PrevDecl) ->getSpecializedTemplate(); } } if (TUK == TUK_Friend) { // C++ [namespace.memdef]p3: // [...] When looking for a prior declaration of a class or a function // declared as a friend, and when the name of the friend class or // function is neither a qualified name nor a template-id, scopes outside // the innermost enclosing namespace scope are not considered. if (!SS.isSet()) { DeclContext *OutermostContext = CurContext; while (!OutermostContext->isFileContext()) OutermostContext = OutermostContext->getLookupParent(); if (PrevDecl && (OutermostContext->Equals(PrevDecl->getDeclContext()) || OutermostContext->Encloses(PrevDecl->getDeclContext()))) { SemanticContext = PrevDecl->getDeclContext(); } else { // Declarations in outer scopes don't matter. However, the outermost // context we computed is the semantic context for our new // declaration. PrevDecl = PrevClassTemplate = 0; SemanticContext = OutermostContext; } } if (CurContext->isDependentContext()) { // If this is a dependent context, we don't want to link the friend // class template to the template in scope, because that would perform // checking of the template parameter lists that can't be performed // until the outer context is instantiated. PrevDecl = PrevClassTemplate = 0; } } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) PrevDecl = PrevClassTemplate = 0; if (PrevClassTemplate) { // Ensure that the template parameter lists are compatible. if (!TemplateParameterListsAreEqual(TemplateParams, PrevClassTemplate->getTemplateParameters(), /*Complain=*/true, TPL_TemplateMatch)) return true; // C++ [temp.class]p4: // In a redeclaration, partial specialization, explicit // specialization or explicit instantiation of a class template, // the class-key shall agree in kind with the original class // template declaration (7.1.5.3). RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { Diag(KWLoc, diag::err_use_with_wrong_tag) << Name << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); Kind = PrevRecordDecl->getTagKind(); } // Check for redefinition of this class template. if (TUK == TUK_Definition) { if (TagDecl *Def = PrevRecordDecl->getDefinition()) { Diag(NameLoc, diag::err_redefinition) << Name; Diag(Def->getLocation(), diag::note_previous_definition); // FIXME: Would it make sense to try to "forget" the previous // definition, as part of error recovery? return true; } } } else if (PrevDecl && PrevDecl->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); // Just pretend that we didn't see the previous declaration. PrevDecl = 0; } else if (PrevDecl) { // C++ [temp]p5: // A class template shall not have the same name as any other // template, class, function, object, enumeration, enumerator, // namespace, or type in the same scope (3.3), except as specified // in (14.5.4). Diag(NameLoc, diag::err_redefinition_different_kind) << Name; Diag(PrevDecl->getLocation(), diag::note_previous_definition); return true; } // Check the template parameter list of this declaration, possibly // merging in the template parameter list from the previous class // template declaration. if (CheckTemplateParameterList(TemplateParams, PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, TPC_ClassTemplate)) Invalid = true; if (SS.isSet()) { // If the name of the template was qualified, we must be defining the // template out-of-line. if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && !(TUK == TUK_Friend && CurContext->isDependentContext())) Diag(NameLoc, diag::err_member_def_does_not_match) << Name << SemanticContext << SS.getRange(); } CXXRecordDecl *NewClass = CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, PrevClassTemplate? PrevClassTemplate->getTemplatedDecl() : 0, /*DelayTypeCreation=*/true); SetNestedNameSpecifier(NewClass, SS); ClassTemplateDecl *NewTemplate = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, DeclarationName(Name), TemplateParams, NewClass, PrevClassTemplate); NewClass->setDescribedClassTemplate(NewTemplate); // Build the type for the class template declaration now. QualType T = NewTemplate->getInjectedClassNameSpecialization(); T = Context.getInjectedClassNameType(NewClass, T); assert(T->isDependentType() && "Class template type is not dependent?"); (void)T; // If we are providing an explicit specialization of a member that is a // class template, make a note of that. if (PrevClassTemplate && PrevClassTemplate->getInstantiatedFromMemberTemplate()) PrevClassTemplate->setMemberSpecialization(); // Set the access specifier. if (!Invalid && TUK != TUK_Friend) SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); // Set the lexical context of these templates NewClass->setLexicalDeclContext(CurContext); NewTemplate->setLexicalDeclContext(CurContext); if (TUK == TUK_Definition) NewClass->startDefinition(); if (Attr) ProcessDeclAttributeList(S, NewClass, Attr); if (TUK != TUK_Friend) PushOnScopeChains(NewTemplate, S); else { if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { NewTemplate->setAccess(PrevClassTemplate->getAccess()); NewClass->setAccess(PrevClassTemplate->getAccess()); } NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevClassTemplate != NULL); // Friend templates are visible in fairly strange ways. if (!CurContext->isDependentContext()) { DeclContext *DC = SemanticContext->getRedeclContext(); DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) PushOnScopeChains(NewTemplate, EnclosingScope, /* AddToContext = */ false); } FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NewClass->getLocation(), NewTemplate, /*FIXME:*/NewClass->getLocation()); Friend->setAccess(AS_public); CurContext->addDecl(Friend); } if (Invalid) { NewTemplate->setInvalidDecl(); NewClass->setInvalidDecl(); } return NewTemplate; } /// \brief Diagnose the presence of a default template argument on a /// template parameter, which is ill-formed in certain contexts. /// /// \returns true if the default template argument should be dropped. static bool DiagnoseDefaultTemplateArgument(Sema &S, Sema::TemplateParamListContext TPC, SourceLocation ParamLoc, SourceRange DefArgRange) { switch (TPC) { case Sema::TPC_ClassTemplate: return false; case Sema::TPC_FunctionTemplate: // C++ [temp.param]p9: // A default template-argument shall not be specified in a // function template declaration or a function template // definition [...] // (This sentence is not in C++0x, per DR226). if (!S.getLangOptions().CPlusPlus0x) S.Diag(ParamLoc, diag::err_template_parameter_default_in_function_template) << DefArgRange; return false; case Sema::TPC_ClassTemplateMember: // C++0x [temp.param]p9: // A default template-argument shall not be specified in the // template-parameter-lists of the definition of a member of a // class template that appears outside of the member's class. S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) << DefArgRange; return true; case Sema::TPC_FriendFunctionTemplate: // C++ [temp.param]p9: // A default template-argument shall not be specified in a // friend template declaration. S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) << DefArgRange; return true; // FIXME: C++0x [temp.param]p9 allows default template-arguments // for friend function templates if there is only a single // declaration (and it is a definition). Strange! } return false; } /// \brief Checks the validity of a template parameter list, possibly /// considering the template parameter list from a previous /// declaration. /// /// If an "old" template parameter list is provided, it must be /// equivalent (per TemplateParameterListsAreEqual) to the "new" /// template parameter list. /// /// \param NewParams Template parameter list for a new template /// declaration. This template parameter list will be updated with any /// default arguments that are carried through from the previous /// template parameter list. /// /// \param OldParams If provided, template parameter list from a /// previous declaration of the same template. Default template /// arguments will be merged from the old template parameter list to /// the new template parameter list. /// /// \param TPC Describes the context in which we are checking the given /// template parameter list. /// /// \returns true if an error occurred, false otherwise. bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, TemplateParameterList *OldParams, TemplateParamListContext TPC) { bool Invalid = false; // C++ [temp.param]p10: // The set of default template-arguments available for use with a // template declaration or definition is obtained by merging the // default arguments from the definition (if in scope) and all // declarations in scope in the same way default function // arguments are (8.3.6). bool SawDefaultArgument = false; SourceLocation PreviousDefaultArgLoc; bool SawParameterPack = false; SourceLocation ParameterPackLoc; // Dummy initialization to avoid warnings. TemplateParameterList::iterator OldParam = NewParams->end(); if (OldParams) OldParam = OldParams->begin(); for (TemplateParameterList::iterator NewParam = NewParams->begin(), NewParamEnd = NewParams->end(); NewParam != NewParamEnd; ++NewParam) { // Variables used to diagnose redundant default arguments bool RedundantDefaultArg = false; SourceLocation OldDefaultLoc; SourceLocation NewDefaultLoc; // Variables used to diagnose missing default arguments bool MissingDefaultArg = false; // C++0x [temp.param]p11: // If a template parameter of a class template is a template parameter pack, // it must be the last template parameter. if (SawParameterPack) { Diag(ParameterPackLoc, diag::err_template_param_pack_must_be_last_template_parameter); Invalid = true; } if (TemplateTypeParmDecl *NewTypeParm = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { // Check the presence of a default argument here. if (NewTypeParm->hasDefaultArgument() && DiagnoseDefaultTemplateArgument(*this, TPC, NewTypeParm->getLocation(), NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() .getSourceRange())) NewTypeParm->removeDefaultArgument(); // Merge default arguments for template type parameters. TemplateTypeParmDecl *OldTypeParm = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; if (NewTypeParm->isParameterPack()) { assert(!NewTypeParm->hasDefaultArgument() && "Parameter packs can't have a default argument!"); SawParameterPack = true; ParameterPackLoc = NewTypeParm->getLocation(); } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && NewTypeParm->hasDefaultArgument()) { OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); SawDefaultArgument = true; RedundantDefaultArg = true; PreviousDefaultArgLoc = NewDefaultLoc; } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { // Merge the default argument from the old declaration to the // new declaration. SawDefaultArgument = true; NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), true); PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); } else if (NewTypeParm->hasDefaultArgument()) { SawDefaultArgument = true; PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); } else if (SawDefaultArgument) MissingDefaultArg = true; } else if (NonTypeTemplateParmDecl *NewNonTypeParm = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { // Check the presence of a default argument here. if (NewNonTypeParm->hasDefaultArgument() && DiagnoseDefaultTemplateArgument(*this, TPC, NewNonTypeParm->getLocation(), NewNonTypeParm->getDefaultArgument()->getSourceRange())) { NewNonTypeParm->removeDefaultArgument(); } // Merge default arguments for non-type template parameters NonTypeTemplateParmDecl *OldNonTypeParm = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && NewNonTypeParm->hasDefaultArgument()) { OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); SawDefaultArgument = true; RedundantDefaultArg = true; PreviousDefaultArgLoc = NewDefaultLoc; } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { // Merge the default argument from the old declaration to the // new declaration. SawDefaultArgument = true; // FIXME: We need to create a new kind of "default argument" // expression that points to a previous template template // parameter. NewNonTypeParm->setDefaultArgument( OldNonTypeParm->getDefaultArgument(), /*Inherited=*/ true); PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); } else if (NewNonTypeParm->hasDefaultArgument()) { SawDefaultArgument = true; PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); } else if (SawDefaultArgument) MissingDefaultArg = true; } else { // Check the presence of a default argument here. TemplateTemplateParmDecl *NewTemplateParm = cast<TemplateTemplateParmDecl>(*NewParam); if (NewTemplateParm->hasDefaultArgument() && DiagnoseDefaultTemplateArgument(*this, TPC, NewTemplateParm->getLocation(), NewTemplateParm->getDefaultArgument().getSourceRange())) NewTemplateParm->removeDefaultArgument(); // Merge default arguments for template template parameters TemplateTemplateParmDecl *OldTemplateParm = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && NewTemplateParm->hasDefaultArgument()) { OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); SawDefaultArgument = true; RedundantDefaultArg = true; PreviousDefaultArgLoc = NewDefaultLoc; } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { // Merge the default argument from the old declaration to the // new declaration. SawDefaultArgument = true; // FIXME: We need to create a new kind of "default argument" expression // that points to a previous template template parameter. NewTemplateParm->setDefaultArgument( OldTemplateParm->getDefaultArgument(), /*Inherited=*/ true); PreviousDefaultArgLoc = OldTemplateParm->getDefaultArgument().getLocation(); } else if (NewTemplateParm->hasDefaultArgument()) { SawDefaultArgument = true; PreviousDefaultArgLoc = NewTemplateParm->getDefaultArgument().getLocation(); } else if (SawDefaultArgument) MissingDefaultArg = true; } if (RedundantDefaultArg) { // C++ [temp.param]p12: // A template-parameter shall not be given default arguments // by two different declarations in the same scope. Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); Invalid = true; } else if (MissingDefaultArg) { // C++ [temp.param]p11: // If a template-parameter has a default template-argument, // all subsequent template-parameters shall have a default // template-argument supplied. Diag((*NewParam)->getLocation(), diag::err_template_param_default_arg_missing); Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); Invalid = true; } // If we have an old template parameter list that we're merging // in, move on to the next parameter. if (OldParams) ++OldParam; } return Invalid; } /// \brief Match the given template parameter lists to the given scope /// specifier, returning the template parameter list that applies to the /// name. /// /// \param DeclStartLoc the start of the declaration that has a scope /// specifier or a template parameter list. /// /// \param SS the scope specifier that will be matched to the given template /// parameter lists. This scope specifier precedes a qualified name that is /// being declared. /// /// \param ParamLists the template parameter lists, from the outermost to the /// innermost template parameter lists. /// /// \param NumParamLists the number of template parameter lists in ParamLists. /// /// \param IsFriend Whether to apply the slightly different rules for /// matching template parameters to scope specifiers in friend /// declarations. /// /// \param IsExplicitSpecialization will be set true if the entity being /// declared is an explicit specialization, false otherwise. /// /// \returns the template parameter list, if any, that corresponds to the /// name that is preceded by the scope specifier @p SS. This template /// parameter list may be have template parameters (if we're declaring a /// template) or may have no template parameters (if we're declaring a /// template specialization), or may be NULL (if we were's declaring isn't /// itself a template). TemplateParameterList * Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, const CXXScopeSpec &SS, TemplateParameterList **ParamLists, unsigned NumParamLists, bool IsFriend, bool &IsExplicitSpecialization, bool &Invalid) { IsExplicitSpecialization = false; // Find the template-ids that occur within the nested-name-specifier. These // template-ids will match up with the template parameter lists. llvm::SmallVector<const TemplateSpecializationType *, 4> TemplateIdsInSpecifier; llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> ExplicitSpecializationsInSpecifier; for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); NNS; NNS = NNS->getPrefix()) { const Type *T = NNS->getAsType(); if (!T) break; // C++0x [temp.expl.spec]p17: // A member or a member template may be nested within many // enclosing class templates. In an explicit specialization for // such a member, the member declaration shall be preceded by a // template<> for each enclosing class template that is // explicitly specialized. // // Following the existing practice of GNU and EDG, we allow a typedef of a // template specialization type. if (const TypedefType *TT = dyn_cast<TypedefType>(T)) T = TT->LookThroughTypedefs().getTypePtr(); if (const TemplateSpecializationType *SpecType = dyn_cast<TemplateSpecializationType>(T)) { TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); if (!Template) continue; // FIXME: should this be an error? probably... if (const RecordType *Record = SpecType->getAs<RecordType>()) { ClassTemplateSpecializationDecl *SpecDecl = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); // If the nested name specifier refers to an explicit specialization, // we don't need a template<> header. if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { ExplicitSpecializationsInSpecifier.push_back(SpecDecl); continue; } } TemplateIdsInSpecifier.push_back(SpecType); } } // Reverse the list of template-ids in the scope specifier, so that we can // more easily match up the template-ids and the template parameter lists. std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); SourceLocation FirstTemplateLoc = DeclStartLoc; if (NumParamLists) FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); // Match the template-ids found in the specifier to the template parameter // lists. unsigned Idx = 0; for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); Idx != NumTemplateIds; ++Idx) { QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); bool DependentTemplateId = TemplateId->isDependentType(); if (Idx >= NumParamLists) { // We have a template-id without a corresponding template parameter // list. // ...which is fine if this is a friend declaration. if (IsFriend) { IsExplicitSpecialization = true; break; } if (DependentTemplateId) { // FIXME: the location information here isn't great. Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_template_parameters) << TemplateId << SS.getRange(); Invalid = true; } else { Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) << SS.getRange() << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); IsExplicitSpecialization = true; } return 0; } // Check the template parameter list against its corresponding template-id. if (DependentTemplateId) { TemplateParameterList *ExpectedTemplateParams = 0; // Are there cases in (e.g.) friends where this won't match? if (const InjectedClassNameType *Injected = TemplateId->getAs<InjectedClassNameType>()) { CXXRecordDecl *Record = Injected->getDecl(); if (ClassTemplatePartialSpecializationDecl *Partial = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) ExpectedTemplateParams = Partial->getTemplateParameters(); else ExpectedTemplateParams = Record->getDescribedClassTemplate() ->getTemplateParameters(); } if (ExpectedTemplateParams) TemplateParameterListsAreEqual(ParamLists[Idx], ExpectedTemplateParams, true, TPL_TemplateMatch); CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); } else if (ParamLists[Idx]->size() > 0) Diag(ParamLists[Idx]->getTemplateLoc(), diag::err_template_param_list_matches_nontemplate) << TemplateId << ParamLists[Idx]->getSourceRange(); else IsExplicitSpecialization = true; } // If there were at least as many template-ids as there were template // parameter lists, then there are no template parameter lists remaining for // the declaration itself. if (Idx >= NumParamLists) return 0; // If there were too many template parameter lists, complain about that now. if (Idx != NumParamLists - 1) { while (Idx < NumParamLists - 1) { bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; Diag(ParamLists[Idx]->getTemplateLoc(), isExplicitSpecHeader? diag::warn_template_spec_extra_headers : diag::err_template_spec_extra_headers) << SourceRange(ParamLists[Idx]->getTemplateLoc(), ParamLists[Idx]->getRAngleLoc()); if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), diag::note_explicit_template_spec_does_not_need_header) << ExplicitSpecializationsInSpecifier.back(); ExplicitSpecializationsInSpecifier.pop_back(); } // We have a template parameter list with no corresponding scope, which // means that the resulting template declaration can't be instantiated // properly (we'll end up with dependent nodes when we shouldn't). if (!isExplicitSpecHeader) Invalid = true; ++Idx; } } // Return the last template parameter list, which corresponds to the // entity being declared. return ParamLists[NumParamLists - 1]; } QualType Sema::CheckTemplateIdType(TemplateName Name, SourceLocation TemplateLoc, const TemplateArgumentListInfo &TemplateArgs) { TemplateDecl *Template = Name.getAsTemplateDecl(); if (!Template) { // The template name does not resolve to a template, so we just // build a dependent template-id type. return Context.getTemplateSpecializationType(Name, TemplateArgs); } // Check that the template argument list is well-formed for this // template. TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), TemplateArgs.size()); if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, false, Converted)) return QualType(); assert((Converted.structuredSize() == Template->getTemplateParameters()->size()) && "Converted template argument list is too short!"); QualType CanonType; if (Name.isDependent() || TemplateSpecializationType::anyDependentTemplateArguments( TemplateArgs)) { // This class template specialization is a dependent // type. Therefore, its canonical type is another class template // specialization type that contains all of the converted // arguments in canonical form. This ensures that, e.g., A<T> and // A<T, T> have identical types when A is declared as: // // template<typename T, typename U = T> struct A; TemplateName CanonName = Context.getCanonicalTemplateName(Name); CanonType = Context.getTemplateSpecializationType(CanonName, Converted.getFlatArguments(), Converted.flatSize()); // FIXME: CanonType is not actually the canonical type, and unfortunately // it is a TemplateSpecializationType that we will never use again. // In the future, we need to teach getTemplateSpecializationType to only // build the canonical type and return that to us. CanonType = Context.getCanonicalType(CanonType); // This might work out to be a current instantiation, in which // case the canonical type needs to be the InjectedClassNameType. // // TODO: in theory this could be a simple hashtable lookup; most // changes to CurContext don't change the set of current // instantiations. if (isa<ClassTemplateDecl>(Template)) { for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { // If we get out to a namespace, we're done. if (Ctx->isFileContext()) break; // If this isn't a record, keep looking. CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); if (!Record) continue; // Look for one of the two cases with InjectedClassNameTypes // and check whether it's the same template. if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && !Record->getDescribedClassTemplate()) continue; // Fetch the injected class name type and check whether its // injected type is equal to the type we just built. QualType ICNT = Context.getTypeDeclType(Record); QualType Injected = cast<InjectedClassNameType>(ICNT) ->getInjectedSpecializationType(); if (CanonType != Injected->getCanonicalTypeInternal()) continue; // If so, the canonical type of this TST is the injected // class name type of the record we just found. assert(ICNT.isCanonical()); CanonType = ICNT; break; } } } else if (ClassTemplateDecl *ClassTemplate = dyn_cast<ClassTemplateDecl>(Template)) { // Find the class template specialization declaration that // corresponds to these arguments. void *InsertPos = 0; ClassTemplateSpecializationDecl *Decl = ClassTemplate->findSpecialization(Converted.getFlatArguments(), Converted.flatSize(), InsertPos); if (!Decl) { // This is the first time we have referenced this class template // specialization. Create the canonical declaration and add it to // the set of specializations. Decl = ClassTemplateSpecializationDecl::Create(Context, ClassTemplate->getTemplatedDecl()->getTagKind(), ClassTemplate->getDeclContext(), ClassTemplate->getLocation(), ClassTemplate, Converted, 0); ClassTemplate->AddSpecialization(Decl, InsertPos); Decl->setLexicalDeclContext(CurContext); } CanonType = Context.getTypeDeclType(Decl); assert(isa<RecordType>(CanonType) && "type of non-dependent specialization is not a RecordType"); } // Build the fully-sugared type for this class template // specialization, which refers back to the class template // specialization we created or found. return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); } TypeResult Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, SourceLocation LAngleLoc, ASTTemplateArgsPtr TemplateArgsIn, SourceLocation RAngleLoc) { TemplateName Template = TemplateD.getAsVal<TemplateName>(); // Translate the parser's template argument list in our AST format. TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); translateTemplateArguments(TemplateArgsIn, TemplateArgs); QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); TemplateArgsIn.release(); if (Result.isNull()) return true; TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); TemplateSpecializationTypeLoc TL = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); TL.setTemplateNameLoc(TemplateLoc); TL.setLAngleLoc(LAngleLoc); TL.setRAngleLoc(RAngleLoc); for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); return CreateParsedType(Result, DI); } TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, TagUseKind TUK, TypeSpecifierType TagSpec, SourceLocation TagLoc) { if (TypeResult.isInvalid()) return ::TypeResult(); // FIXME: preserve source info, ideally without copying the DI. TypeSourceInfo *DI; QualType Type = GetTypeFromParser(TypeResult.get(), &DI); // Verify the tag specifier. TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); if (const RecordType *RT = Type->getAs<RecordType>()) { RecordDecl *D = RT->getDecl(); IdentifierInfo *Id = D->getIdentifier(); assert(Id && "templated class must have an identifier"); if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { Diag(TagLoc, diag::err_use_with_wrong_tag) << Type << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); Diag(D->getLocation(), diag::note_previous_use); } } ElaboratedTypeKeyword Keyword = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type); return ParsedType::make(ElabType); } ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, LookupResult &R, bool RequiresADL, const TemplateArgumentListInfo &TemplateArgs) { // FIXME: Can we do any checking at this point? I guess we could check the // template arguments that we have against the template name, if the template // name refers to a single template. That's not a terribly common case, // though. // These should be filtered out by our callers. assert(!R.empty() && "empty lookup results when building templateid"); assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); NestedNameSpecifier *Qualifier = 0; SourceRange QualifierRange; if (SS.isSet()) { Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); QualifierRange = SS.getRange(); } // We don't want lookup warnings at this point. R.suppressDiagnostics(); bool Dependent = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), &TemplateArgs); UnresolvedLookupExpr *ULE = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), Qualifier, QualifierRange, R.getLookupNameInfo(), RequiresADL, TemplateArgs, R.begin(), R.end()); return Owned(ULE); } // We actually only call this from template instantiation. ExprResult Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, const TemplateArgumentListInfo &TemplateArgs) { DeclContext *DC; if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext() || RequireCompleteDeclContext(SS, DC)) return BuildDependentDeclRefExpr(SS, NameInfo, &TemplateArgs); bool MemberOfUnknownSpecialization; LookupResult R(*this, NameInfo, LookupOrdinaryName); LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, MemberOfUnknownSpecialization); if (R.isAmbiguous()) return ExprError(); if (R.empty()) { Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template) << NameInfo.getName() << SS.getRange(); return ExprError(); } if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template) << (NestedNameSpecifier*) SS.getScopeRep() << NameInfo.getName() << SS.getRange(); Diag(Temp->getLocation(), diag::note_referenced_class_template); return ExprError(); } return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); } /// \brief Form a dependent template name. /// /// This action forms a dependent template name given the template /// name and its (presumably dependent) scope specifier. For /// example, given "MetaFun::template apply", the scope specifier \p /// SS will be "MetaFun::", \p TemplateKWLoc contains the location /// of the "template" keyword, and "apply" is the \p Name. TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S, SourceLocation TemplateKWLoc, CXXScopeSpec &SS, UnqualifiedId &Name, ParsedType ObjectType, bool EnteringContext, TemplateTy &Result) { if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() && !getLangOptions().CPlusPlus0x) Diag(TemplateKWLoc, diag::ext_template_outside_of_template) << FixItHint::CreateRemoval(TemplateKWLoc); DeclContext *LookupCtx = 0; if (SS.isSet()) LookupCtx = computeDeclContext(SS, EnteringContext); if (!LookupCtx && ObjectType) LookupCtx = computeDeclContext(ObjectType.get()); if (LookupCtx) { // C++0x [temp.names]p5: // If a name prefixed by the keyword template is not the name of // a template, the program is ill-formed. [Note: the keyword // template may not be applied to non-template members of class // templates. -end note ] [ Note: as is the case with the // typename prefix, the template prefix is allowed in cases // where it is not strictly necessary; i.e., when the // nested-name-specifier or the expression on the left of the -> // or . is not dependent on a template-parameter, or the use // does not appear in the scope of a template. -end note] // // Note: C++03 was more strict here, because it banned the use of // the "template" keyword prior to a template-name that was not a // dependent name. C++ DR468 relaxed this requirement (the // "template" keyword is now permitted). We follow the C++0x // rules, even in C++03 mode with a warning, retroactively applying the DR. bool MemberOfUnknownSpecialization; TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name, ObjectType, EnteringContext, Result, MemberOfUnknownSpecialization); if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && isa<CXXRecordDecl>(LookupCtx) && cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { // This is a dependent template. Handle it below. } else if (TNK == TNK_Non_template) { Diag(Name.getSourceRange().getBegin(), diag::err_template_kw_refers_to_non_template) << GetNameFromUnqualifiedId(Name).getName() << Name.getSourceRange() << TemplateKWLoc; return TNK_Non_template; } else { // We found something; return it. return TNK; } } NestedNameSpecifier *Qualifier = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); switch (Name.getKind()) { case UnqualifiedId::IK_Identifier: Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, Name.Identifier)); return TNK_Dependent_template_name; case UnqualifiedId::IK_OperatorFunctionId: Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, Name.OperatorFunctionId.Operator)); return TNK_Dependent_template_name; case UnqualifiedId::IK_LiteralOperatorId: assert(false && "We don't support these; Parse shouldn't have allowed propagation"); default: break; } Diag(Name.getSourceRange().getBegin(), diag::err_template_kw_refers_to_non_template) << GetNameFromUnqualifiedId(Name).getName() << Name.getSourceRange() << TemplateKWLoc; return TNK_Non_template; } bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, const TemplateArgumentLoc &AL, TemplateArgumentListBuilder &Converted) { const TemplateArgument &Arg = AL.getArgument(); // Check template type parameter. switch(Arg.getKind()) { case TemplateArgument::Type: // C++ [temp.arg.type]p1: // A template-argument for a template-parameter which is a // type shall be a type-id. break; case TemplateArgument::Template: { // We have a template type parameter but the template argument // is a template without any arguments. SourceRange SR = AL.getSourceRange(); TemplateName Name = Arg.getAsTemplate(); Diag(SR.getBegin(), diag::err_template_missing_args) << Name << SR; if (TemplateDecl *Decl = Name.getAsTemplateDecl()) Diag(Decl->getLocation(), diag::note_template_decl_here); return true; } default: { // We have a template type parameter but the template argument // is not a type. SourceRange SR = AL.getSourceRange(); Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; Diag(Param->getLocation(), diag::note_template_param_here); return true; } } if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) return true; // Add the converted template type argument. Converted.Append( TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); return false; } /// \brief Substitute template arguments into the default template argument for /// the given template type parameter. /// /// \param SemaRef the semantic analysis object for which we are performing /// the substitution. /// /// \param Template the template that we are synthesizing template arguments /// for. /// /// \param TemplateLoc the location of the template name that started the /// template-id we are checking. /// /// \param RAngleLoc the location of the right angle bracket ('>') that /// terminates the template-id. /// /// \param Param the template template parameter whose default we are /// substituting into. /// /// \param Converted the list of template arguments provided for template /// parameters that precede \p Param in the template parameter list. /// /// \returns the substituted template argument, or NULL if an error occurred. static TypeSourceInfo * SubstDefaultTemplateArgument(Sema &SemaRef, TemplateDecl *Template, SourceLocation TemplateLoc, SourceLocation RAngleLoc, TemplateTypeParmDecl *Param, TemplateArgumentListBuilder &Converted) { TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); // If the argument type is dependent, instantiate it now based // on the previously-computed template arguments. if (ArgType->getType()->isDependentType()) { TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, /*TakeArgs=*/false); MultiLevelTemplateArgumentList AllTemplateArgs = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, Template, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, Param->getDefaultArgumentLoc(), Param->getDeclName()); } return ArgType; } /// \brief Substitute template arguments into the default template argument for /// the given non-type template parameter. /// /// \param SemaRef the semantic analysis object for which we are performing /// the substitution. /// /// \param Template the template that we are synthesizing template arguments /// for. /// /// \param TemplateLoc the location of the template name that started the /// template-id we are checking. /// /// \param RAngleLoc the location of the right angle bracket ('>') that /// terminates the template-id. /// /// \param Param the non-type template parameter whose default we are /// substituting into. /// /// \param Converted the list of template arguments provided for template /// parameters that precede \p Param in the template parameter list. /// /// \returns the substituted template argument, or NULL if an error occurred. static ExprResult SubstDefaultTemplateArgument(Sema &SemaRef, TemplateDecl *Template, SourceLocation TemplateLoc, SourceLocation RAngleLoc, NonTypeTemplateParmDecl *Param, TemplateArgumentListBuilder &Converted) { TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, /*TakeArgs=*/false); MultiLevelTemplateArgumentList AllTemplateArgs = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, Template, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); } /// \brief Substitute template arguments into the default template argument for /// the given template template parameter. /// /// \param SemaRef the semantic analysis object for which we are performing /// the substitution. /// /// \param Template the template that we are synthesizing template arguments /// for. /// /// \param TemplateLoc the location of the template name that started the /// template-id we are checking. /// /// \param RAngleLoc the location of the right angle bracket ('>') that /// terminates the template-id. /// /// \param Param the template template parameter whose default we are /// substituting into. /// /// \param Converted the list of template arguments provided for template /// parameters that precede \p Param in the template parameter list. /// /// \returns the substituted template argument, or NULL if an error occurred. static TemplateName SubstDefaultTemplateArgument(Sema &SemaRef, TemplateDecl *Template, SourceLocation TemplateLoc, SourceLocation RAngleLoc, TemplateTemplateParmDecl *Param, TemplateArgumentListBuilder &Converted) { TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, /*TakeArgs=*/false); MultiLevelTemplateArgumentList AllTemplateArgs = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, Template, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); return SemaRef.SubstTemplateName( Param->getDefaultArgument().getArgument().getAsTemplate(), Param->getDefaultArgument().getTemplateNameLoc(), AllTemplateArgs); } /// \brief If the given template parameter has a default template /// argument, substitute into that default template argument and /// return the corresponding template argument. TemplateArgumentLoc Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, SourceLocation TemplateLoc, SourceLocation RAngleLoc, Decl *Param, TemplateArgumentListBuilder &Converted) { if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { if (!TypeParm->hasDefaultArgument()) return TemplateArgumentLoc(); TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, TypeParm, Converted); if (DI) return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); return TemplateArgumentLoc(); } if (NonTypeTemplateParmDecl *NonTypeParm = dyn_cast<NonTypeTemplateParmDecl>(Param)) { if (!NonTypeParm->hasDefaultArgument()) return TemplateArgumentLoc(); ExprResult Arg = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, NonTypeParm, Converted); if (Arg.isInvalid()) return TemplateArgumentLoc(); Expr *ArgE = Arg.takeAs<Expr>(); return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); } TemplateTemplateParmDecl *TempTempParm = cast<TemplateTemplateParmDecl>(Param); if (!TempTempParm->hasDefaultArgument()) return TemplateArgumentLoc(); TemplateName TName = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, TempTempParm, Converted); if (TName.isNull()) return TemplateArgumentLoc(); return TemplateArgumentLoc(TemplateArgument(TName), TempTempParm->getDefaultArgument().getTemplateQualifierRange(), TempTempParm->getDefaultArgument().getTemplateNameLoc()); } /// \brief Check that the given template argument corresponds to the given /// template parameter. bool Sema::CheckTemplateArgument(NamedDecl *Param, const TemplateArgumentLoc &Arg, TemplateDecl *Template, SourceLocation TemplateLoc, SourceLocation RAngleLoc, TemplateArgumentListBuilder &Converted, CheckTemplateArgumentKind CTAK) { // Check template type parameters. if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) return CheckTemplateTypeArgument(TTP, Arg, Converted); // Check non-type template parameters. if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { // Do substitution on the type of the non-type template parameter // with the template arguments we've seen thus far. QualType NTTPType = NTTP->getType(); if (NTTPType->isDependentType()) { // Do substitution on the type of the non-type template parameter. InstantiatingTemplate Inst(*this, TemplateLoc, Template, NTTP, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); TemplateArgumentList TemplateArgs(Context, Converted, /*TakeArgs=*/false); NTTPType = SubstType(NTTPType, MultiLevelTemplateArgumentList(TemplateArgs), NTTP->getLocation(), NTTP->getDeclName()); // If that worked, check the non-type template parameter type // for validity. if (!NTTPType.isNull()) NTTPType = CheckNonTypeTemplateParameterType(NTTPType, NTTP->getLocation()); if (NTTPType.isNull()) return true; } switch (Arg.getArgument().getKind()) { case TemplateArgument::Null: assert(false && "Should never see a NULL template argument here"); return true; case TemplateArgument::Expression: { Expr *E = Arg.getArgument().getAsExpr(); TemplateArgument Result; if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) return true; Converted.Append(Result); break; } case TemplateArgument::Declaration: case TemplateArgument::Integral: // We've already checked this template argument, so just copy // it to the list of converted arguments. Converted.Append(Arg.getArgument()); break; case TemplateArgument::Template: // We were given a template template argument. It may not be ill-formed; // see below. if (DependentTemplateName *DTN = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { // We have a template argument such as \c T::template X, which we // parsed as a template template argument. However, since we now // know that we need a non-type template argument, convert this // template name into an expression. DeclarationNameInfo NameInfo(DTN->getIdentifier(), Arg.getTemplateNameLoc()); Expr *E = DependentScopeDeclRefExpr::Create(Context, DTN->getQualifier(), Arg.getTemplateQualifierRange(), NameInfo); TemplateArgument Result; if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) return true; Converted.Append(Result); break; } // We have a template argument that actually does refer to a class // template, template alias, or template template parameter, and // therefore cannot be a non-type template argument. Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) << Arg.getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; case TemplateArgument::Type: { // We have a non-type template parameter but the template // argument is a type. // C++ [temp.arg]p2: // In a template-argument, an ambiguity between a type-id and // an expression is resolved to a type-id, regardless of the // form of the corresponding template-parameter. // // We warn specifically about this case, since it can be rather // confusing for users. QualType T = Arg.getArgument().getAsType(); SourceRange SR = Arg.getSourceRange(); if (T->isFunctionType()) Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; else Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; Diag(Param->getLocation(), diag::note_template_param_here); return true; } case TemplateArgument::Pack: llvm_unreachable("Caller must expand template argument packs"); break; } return false; } // Check template template parameters. TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); // Substitute into the template parameter list of the template // template parameter, since previously-supplied template arguments // may appear within the template template parameter. { // Set up a template instantiation context. LocalInstantiationScope Scope(*this); InstantiatingTemplate Inst(*this, TemplateLoc, Template, TempParm, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); TemplateArgumentList TemplateArgs(Context, Converted, /*TakeArgs=*/false); TempParm = cast_or_null<TemplateTemplateParmDecl>( SubstDecl(TempParm, CurContext, MultiLevelTemplateArgumentList(TemplateArgs))); if (!TempParm) return true; // FIXME: TempParam is leaked. } switch (Arg.getArgument().getKind()) { case TemplateArgument::Null: assert(false && "Should never see a NULL template argument here"); return true; case TemplateArgument::Template: if (CheckTemplateArgument(TempParm, Arg)) return true; Converted.Append(Arg.getArgument()); break; case TemplateArgument::Expression: case TemplateArgument::Type: // We have a template template parameter but the template // argument does not refer to a template. Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); return true; case TemplateArgument::Declaration: llvm_unreachable( "Declaration argument with template template parameter"); break; case TemplateArgument::Integral: llvm_unreachable( "Integral argument with template template parameter"); break; case TemplateArgument::Pack: llvm_unreachable("Caller must expand template argument packs"); break; } return false; } /// \brief Check that the given template argument list is well-formed /// for specializing the given template. bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, SourceLocation TemplateLoc, const TemplateArgumentListInfo &TemplateArgs, bool PartialTemplateArgs, TemplateArgumentListBuilder &Converted) { TemplateParameterList *Params = Template->getTemplateParameters(); unsigned NumParams = Params->size(); unsigned NumArgs = TemplateArgs.size(); bool Invalid = false; SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); bool HasParameterPack = NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); if ((NumArgs > NumParams && !HasParameterPack) || (NumArgs < Params->getMinRequiredArguments() && !PartialTemplateArgs)) { // FIXME: point at either the first arg beyond what we can handle, // or the '>', depending on whether we have too many or too few // arguments. SourceRange Range; if (NumArgs > NumParams) Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); Diag(TemplateLoc, diag::err_template_arg_list_different_arity) << (NumArgs > NumParams) << (isa<ClassTemplateDecl>(Template)? 0 : isa<FunctionTemplateDecl>(Template)? 1 : isa<TemplateTemplateParmDecl>(Template)? 2 : 3) << Template << Range; Diag(Template->getLocation(), diag::note_template_decl_here) << Params->getSourceRange(); Invalid = true; } // C++ [temp.arg]p1: // [...] The type and form of each template-argument specified in // a template-id shall match the type and form specified for the // corresponding parameter declared by the template in its // template-parameter-list. unsigned ArgIdx = 0; for (TemplateParameterList::iterator Param = Params->begin(), ParamEnd = Params->end(); Param != ParamEnd; ++Param, ++ArgIdx) { if (ArgIdx > NumArgs && PartialTemplateArgs) break; // If we have a template parameter pack, check every remaining template // argument against that template parameter pack. if ((*Param)->isTemplateParameterPack()) { Converted.BeginPack(); for (; ArgIdx < NumArgs; ++ArgIdx) { if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, TemplateLoc, RAngleLoc, Converted)) { Invalid = true; break; } } Converted.EndPack(); continue; } if (ArgIdx < NumArgs) { // Check the template argument we were given. if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, TemplateLoc, RAngleLoc, Converted)) return true; continue; } // We have a default template argument that we will use. TemplateArgumentLoc Arg; // Retrieve the default template argument from the template // parameter. For each kind of template parameter, we substitute the // template arguments provided thus far and any "outer" template arguments // (when the template parameter was part of a nested template) into // the default argument. if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { if (!TTP->hasDefaultArgument()) { assert((Invalid || PartialTemplateArgs) && "Missing default argument"); break; } TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, TTP, Converted); if (!ArgType) return true; Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), ArgType); } else if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { if (!NTTP->hasDefaultArgument()) { assert((Invalid || PartialTemplateArgs) && "Missing default argument"); break; } ExprResult E = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, NTTP, Converted); if (E.isInvalid()) return true; Expr *Ex = E.takeAs<Expr>(); Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); } else { TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(*Param); if (!TempParm->hasDefaultArgument()) { assert((Invalid || PartialTemplateArgs) && "Missing default argument"); break; } TemplateName Name = SubstDefaultTemplateArgument(*this, Template, TemplateLoc, RAngleLoc, TempParm, Converted); if (Name.isNull()) return true; Arg = TemplateArgumentLoc(TemplateArgument(Name), TempParm->getDefaultArgument().getTemplateQualifierRange(), TempParm->getDefaultArgument().getTemplateNameLoc()); } // Introduce an instantiation record that describes where we are using // the default template argument. InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, Converted.getFlatArguments(), Converted.flatSize(), SourceRange(TemplateLoc, RAngleLoc)); // Check the default template argument. if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, RAngleLoc, Converted)) return true; } return Invalid; } /// \brief Check a template argument against its corresponding /// template type parameter. /// /// This routine implements the semantics of C++ [temp.arg.type]. It /// returns true if an error occurred, and false otherwise. bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, TypeSourceInfo *ArgInfo) { assert(ArgInfo && "invalid TypeSourceInfo"); QualType Arg = ArgInfo->getType(); // C++03 [temp.arg.type]p2: // A local type, a type with no linkage, an unnamed type or a type // compounded from any of these types shall not be used as a // template-argument for a template type-parameter. // C++0x allows these, and even in C++03 we allow them as an extension with // a warning. SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); if (!LangOpts.CPlusPlus0x) { const TagType *Tag = 0; if (const EnumType *EnumT = Arg->getAs<EnumType>()) Tag = EnumT; else if (const RecordType *RecordT = Arg->getAs<RecordType>()) Tag = RecordT; if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); Diag(SR.getBegin(), diag::ext_template_arg_local_type) << QualType(Tag, 0) << SR; } else if (Tag && !Tag->getDecl()->getDeclName() && !Tag->getDecl()->getTypedefForAnonDecl()) { Diag(SR.getBegin(), diag::ext_template_arg_unnamed_type) << SR; Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); } } if (Arg->isVariablyModifiedType()) { return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg; } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; } return false; } /// \brief Checks whether the given template argument is the address /// of an object or function according to C++ [temp.arg.nontype]p1. static bool CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, NonTypeTemplateParmDecl *Param, QualType ParamType, Expr *ArgIn, TemplateArgument &Converted) { bool Invalid = false; Expr *Arg = ArgIn; QualType ArgType = Arg->getType(); // See through any implicit casts we added to fix the type. while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) Arg = Cast->getSubExpr(); // C++ [temp.arg.nontype]p1: // // A template-argument for a non-type, non-template // template-parameter shall be one of: [...] // // -- the address of an object or function with external // linkage, including function templates and function // template-ids but excluding non-static class members, // expressed as & id-expression where the & is optional if // the name refers to a function or array, or if the // corresponding template-parameter is a reference; or DeclRefExpr *DRE = 0; // Ignore (and complain about) any excess parentheses. while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { if (!Invalid) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_extra_parens) << Arg->getSourceRange(); Invalid = true; } Arg = Parens->getSubExpr(); } bool AddressTaken = false; SourceLocation AddrOpLoc; if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { if (UnOp->getOpcode() == UO_AddrOf) { DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); AddressTaken = true; AddrOpLoc = UnOp->getOperatorLoc(); } } else DRE = dyn_cast<DeclRefExpr>(Arg); if (!DRE) { S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } // Stop checking the precise nature of the argument if it is value dependent, // it should be checked when instantiated. if (Arg->isValueDependent()) { Converted = TemplateArgument(ArgIn->Retain()); return false; } if (!isa<ValueDecl>(DRE->getDecl())) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_object_or_func_form) << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } NamedDecl *Entity = 0; // Cannot refer to non-static data members if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) << Field << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } // Cannot refer to non-static member functions if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) if (!Method->isStatic()) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) << Method << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } // Functions must have external linkage. if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { if (!isExternalLinkage(Func->getLinkage())) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_function_not_extern) << Func << Arg->getSourceRange(); S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) << true; return true; } // Okay: we've named a function with external linkage. Entity = Func; // If the template parameter has pointer type, the function decays. if (ParamType->isPointerType() && !AddressTaken) ArgType = S.Context.getPointerType(Func->getType()); else if (AddressTaken && ParamType->isReferenceType()) { // If we originally had an address-of operator, but the // parameter has reference type, complain and (if things look // like they will work) drop the address-of operator. if (!S.Context.hasSameUnqualifiedType(Func->getType(), ParamType.getNonReferenceType())) { S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) << ParamType; S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) << ParamType << FixItHint::CreateRemoval(AddrOpLoc); S.Diag(Param->getLocation(), diag::note_template_param_here); ArgType = Func->getType(); } } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { if (!isExternalLinkage(Var->getLinkage())) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_object_not_extern) << Var << Arg->getSourceRange(); S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) << true; return true; } // A value of reference type is not an object. if (Var->getType()->isReferenceType()) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_reference_var) << Var->getType() << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } // Okay: we've named an object with external linkage Entity = Var; // If the template parameter has pointer type, we must have taken // the address of this object. if (ParamType->isReferenceType()) { if (AddressTaken) { // If we originally had an address-of operator, but the // parameter has reference type, complain and (if things look // like they will work) drop the address-of operator. if (!S.Context.hasSameUnqualifiedType(Var->getType(), ParamType.getNonReferenceType())) { S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) << ParamType; S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) << ParamType << FixItHint::CreateRemoval(AddrOpLoc); S.Diag(Param->getLocation(), diag::note_template_param_here); ArgType = Var->getType(); } } else if (!AddressTaken && ParamType->isPointerType()) { if (Var->getType()->isArrayType()) { // Array-to-pointer decay. ArgType = S.Context.getArrayDecayedType(Var->getType()); } else { // If the template parameter has pointer type but the address of // this object was not taken, complain and (possibly) recover by // taking the address of the entity. ArgType = S.Context.getPointerType(Var->getType()); if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) << ParamType; S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) << ParamType << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); S.Diag(Param->getLocation(), diag::note_template_param_here); } } } else { // We found something else, but we don't know specifically what it is. S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_object_or_func) << Arg->getSourceRange(); S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); return true; } if (ParamType->isPointerType() && !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && S.IsQualificationConversion(ArgType, ParamType)) { // For pointer-to-object types, qualification conversions are // permitted. } else { if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { if (!ParamRef->getPointeeType()->isFunctionType()) { // C++ [temp.arg.nontype]p5b3: // For a non-type template-parameter of type reference to // object, no conversions apply. The type referred to by the // reference may be more cv-qualified than the (otherwise // identical) type of the template- argument. The // template-parameter is bound directly to the // template-argument, which shall be an lvalue. // FIXME: Other qualifiers? unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); unsigned ArgQuals = ArgType.getCVRQualifiers(); if ((ParamQuals | ArgQuals) != ParamQuals) { S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_ref_bind_ignores_quals) << ParamType << Arg->getType() << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } } } // At this point, the template argument refers to an object or // function with external linkage. We now need to check whether the // argument and parameter types are compatible. if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType.getNonReferenceType())) { // We can't perform this conversion or binding. if (ParamType->isReferenceType()) S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) << ParamType << Arg->getType() << Arg->getSourceRange(); else S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) << Arg->getType() << ParamType << Arg->getSourceRange(); S.Diag(Param->getLocation(), diag::note_template_param_here); return true; } } // Create the template argument. Converted = TemplateArgument(Entity->getCanonicalDecl()); S.MarkDeclarationReferenced(Arg->getLocStart(), Entity); return false; } /// \brief Checks whether the given template argument is a pointer to /// member constant according to C++ [temp.arg.nontype]p1. bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, TemplateArgument &Converted) { bool Invalid = false; // See through any implicit casts we added to fix the type. while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) Arg = Cast->getSubExpr(); // C++ [temp.arg.nontype]p1: // // A template-argument for a non-type, non-template // template-parameter shall be one of: [...] // // -- a pointer to member expressed as described in 5.3.1. DeclRefExpr *DRE = 0; // Ignore (and complain about) any excess parentheses. while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { if (!Invalid) { Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_extra_parens) << Arg->getSourceRange(); Invalid = true; } Arg = Parens->getSubExpr(); } // A pointer-to-member constant written &Class::member. if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { if (UnOp->getOpcode() == UO_AddrOf) { DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); if (DRE && !DRE->getQualifier()) DRE = 0; } } // A constant of pointer-to-member type. else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { if (VD->getType()->isMemberPointerType()) { if (isa<NonTypeTemplateParmDecl>(VD) || (isa<VarDecl>(VD) && Context.getCanonicalType(VD->getType()).isConstQualified())) { if (Arg->isTypeDependent() || Arg->isValueDependent()) Converted = TemplateArgument(Arg->Retain()); else Converted = TemplateArgument(VD->getCanonicalDecl()); return Invalid; } } } DRE = 0; } if (!DRE) return Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_pointer_to_member_form) << Arg->getSourceRange(); if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { assert((isa<FieldDecl>(DRE->getDecl()) || !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && "Only non-static member pointers can make it here"); // Okay: this is the address of a non-static member, and therefore // a member pointer constant. if (Arg->isTypeDependent() || Arg->isValueDependent()) Converted = TemplateArgument(Arg->Retain()); else Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); return Invalid; } // We found something else, but we don't know specifically what it is. Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_pointer_to_member_form) << Arg->getSourceRange(); Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); return true; } /// \brief Check a template argument against its corresponding /// non-type template parameter. /// /// This routine implements the semantics of C++ [temp.arg.nontype]. /// It returns true if an error occurred, and false otherwise. \p /// InstantiatedParamType is the type of the non-type template /// parameter after it has been instantiated. /// /// If no error was detected, Converted receives the converted template argument. bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, QualType InstantiatedParamType, Expr *&Arg, TemplateArgument &Converted, CheckTemplateArgumentKind CTAK) { SourceLocation StartLoc = Arg->getSourceRange().getBegin(); // If either the parameter has a dependent type or the argument is // type-dependent, there's nothing we can check now. if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { // FIXME: Produce a cloned, canonical expression? Converted = TemplateArgument(Arg); return false; } // C++ [temp.arg.nontype]p5: // The following conversions are performed on each expression used // as a non-type template-argument. If a non-type // template-argument cannot be converted to the type of the // corresponding template-parameter then the program is // ill-formed. // // -- for a non-type template-parameter of integral or // enumeration type, integral promotions (4.5) and integral // conversions (4.7) are applied. QualType ParamType = InstantiatedParamType; QualType ArgType = Arg->getType(); if (ParamType->isIntegralOrEnumerationType()) { // C++ [temp.arg.nontype]p1: // A template-argument for a non-type, non-template // template-parameter shall be one of: // // -- an integral constant-expression of integral or enumeration // type; or // -- the name of a non-type template-parameter; or SourceLocation NonConstantLoc; llvm::APSInt Value; if (!ArgType->isIntegralOrEnumerationType()) { Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_integral_or_enumeral) << ArgType << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; } else if (!Arg->isValueDependent() && !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { Diag(NonConstantLoc, diag::err_template_arg_not_ice) << ArgType << Arg->getSourceRange(); return true; } // From here on out, all we care about are the unqualified forms // of the parameter and argument types. ParamType = ParamType.getUnqualifiedType(); ArgType = ArgType.getUnqualifiedType(); // Try to convert the argument to the parameter's type. if (Context.hasSameType(ParamType, ArgType)) { // Okay: no conversion necessary } else if (CTAK == CTAK_Deduced) { // C++ [temp.deduct.type]p17: // If, in the declaration of a function template with a non-type // template-parameter, the non-type template- parameter is used // in an expression in the function parameter-list and, if the // corresponding template-argument is deduced, the // template-argument type shall match the type of the // template-parameter exactly, except that a template-argument // deduced from an array bound may be of any integral type. Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) << ArgType << ParamType; Diag(Param->getLocation(), diag::note_template_param_here); return true; } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || !ParamType->isEnumeralType()) { // This is an integral promotion or conversion. ImpCastExprToType(Arg, ParamType, CK_IntegralCast); } else { // We can't perform this conversion. Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_convertible) << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; } QualType IntegerType = Context.getCanonicalType(ParamType); if (const EnumType *Enum = IntegerType->getAs<EnumType>()) IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); if (!Arg->isValueDependent()) { llvm::APSInt OldValue = Value; // Coerce the template argument's value to the value it will have // based on the template parameter's type. unsigned AllowedBits = Context.getTypeSize(IntegerType); if (Value.getBitWidth() != AllowedBits) Value.extOrTrunc(AllowedBits); Value.setIsSigned(IntegerType->isSignedIntegerType()); // Complain if an unsigned parameter received a negative value. if (IntegerType->isUnsignedIntegerType() && (OldValue.isSigned() && OldValue.isNegative())) { Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) << OldValue.toString(10) << Value.toString(10) << Param->getType() << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); } // Complain if we overflowed the template parameter's type. unsigned RequiredBits; if (IntegerType->isUnsignedIntegerType()) RequiredBits = OldValue.getActiveBits(); else if (OldValue.isUnsigned()) RequiredBits = OldValue.getActiveBits() + 1; else RequiredBits = OldValue.getMinSignedBits(); if (RequiredBits > AllowedBits) { Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_too_large) << OldValue.toString(10) << Value.toString(10) << Param->getType() << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); } } // Add the value of this argument to the list of converted // arguments. We use the bitwidth and signedness of the template // parameter. if (Arg->isValueDependent()) { // The argument is value-dependent. Create a new // TemplateArgument with the converted expression. Converted = TemplateArgument(Arg); return false; } Converted = TemplateArgument(Value, ParamType->isEnumeralType() ? ParamType : IntegerType); return false; } DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion // from a template argument of type std::nullptr_t to a non-type // template parameter of type pointer to object, pointer to // function, or pointer-to-member, respectively. if (ArgType->isNullPtrType() && (ParamType->isPointerType() || ParamType->isMemberPointerType())) { Converted = TemplateArgument((NamedDecl *)0); return false; } // Handle pointer-to-function, reference-to-function, and // pointer-to-member-function all in (roughly) the same way. if (// -- For a non-type template-parameter of type pointer to // function, only the function-to-pointer conversion (4.3) is // applied. If the template-argument represents a set of // overloaded functions (or a pointer to such), the matching // function is selected from the set (13.4). (ParamType->isPointerType() && ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || // -- For a non-type template-parameter of type reference to // function, no conversions apply. If the template-argument // represents a set of overloaded functions, the matching // function is selected from the set (13.4). (ParamType->isReferenceType() && ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || // -- For a non-type template-parameter of type pointer to // member function, no conversions apply. If the // template-argument represents a set of overloaded member // functions, the matching member function is selected from // the set (13.4). (ParamType->isMemberPointerType() && ParamType->getAs<MemberPointerType>()->getPointeeType() ->isFunctionType())) { if (Arg->getType() == Context.OverloadTy) { if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, true, FoundResult)) { if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) return true; Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); ArgType = Arg->getType(); } else return true; } if (!ParamType->isMemberPointerType()) return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, ParamType, Arg, Converted); if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); } else if (!Context.hasSameUnqualifiedType(ArgType, ParamType.getNonReferenceType())) { // We can't perform this conversion. Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_convertible) << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; } return CheckTemplateArgumentPointerToMember(Arg, Converted); } if (ParamType->isPointerType()) { // -- for a non-type template-parameter of type pointer to // object, qualification conversions (4.4) and the // array-to-pointer conversion (4.2) are applied. // C++0x also allows a value of std::nullptr_t. assert(ParamType->getPointeeType()->isIncompleteOrObjectType() && "Only object pointers allowed here"); return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, ParamType, Arg, Converted); } if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { // -- For a non-type template-parameter of type reference to // object, no conversions apply. The type referred to by the // reference may be more cv-qualified than the (otherwise // identical) type of the template-argument. The // template-parameter is bound directly to the // template-argument, which must be an lvalue. assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() && "Only object references allowed here"); if (Arg->getType() == Context.OverloadTy) { if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamRefType->getPointeeType(), true, FoundResult)) { if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) return true; Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); ArgType = Arg->getType(); } else return true; } return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, ParamType, Arg, Converted); } // -- For a non-type template-parameter of type pointer to data // member, qualification conversions (4.4) are applied. assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { // Types match exactly: nothing more to do here. } else if (IsQualificationConversion(ArgType, ParamType)) { ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); } else { // We can't perform this conversion. Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_not_convertible) << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; } return CheckTemplateArgumentPointerToMember(Arg, Converted); } /// \brief Check a template argument against its corresponding /// template template parameter. /// /// This routine implements the semantics of C++ [temp.arg.template]. /// It returns true if an error occurred, and false otherwise. bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, const TemplateArgumentLoc &Arg) { TemplateName Name = Arg.getArgument().getAsTemplate(); TemplateDecl *Template = Name.getAsTemplateDecl(); if (!Template) { // Any dependent template name is fine. assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); return false; } // C++ [temp.arg.template]p1: // A template-argument for a template template-parameter shall be // the name of a class template, expressed as id-expression. Only // primary class templates are considered when matching the // template template argument with the corresponding parameter; // partial specializations are not considered even if their // parameter lists match that of the template template parameter. // // Note that we also allow template template parameters here, which // will happen when we are dealing with, e.g., class template // partial specializations. if (!isa<ClassTemplateDecl>(Template) && !isa<TemplateTemplateParmDecl>(Template)) { assert(isa<FunctionTemplateDecl>(Template) && "Only function templates are possible here"); Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) << Template; } return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), Param->getTemplateParameters(), true, TPL_TemplateTemplateArgumentMatch, Arg.getLocation()); } /// \brief Given a non-type template argument that refers to a /// declaration and the type of its corresponding non-type template /// parameter, produce an expression that properly refers to that /// declaration. ExprResult Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, QualType ParamType, SourceLocation Loc) { assert(Arg.getKind() == TemplateArgument::Declaration && "Only declaration template arguments permitted here"); ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); if (VD->getDeclContext()->isRecord() && (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { // If the value is a class member, we might have a pointer-to-member. // Determine whether the non-type template template parameter is of // pointer-to-member type. If so, we need to build an appropriate // expression for a pointer-to-member, since a "normal" DeclRefExpr // would refer to the member itself. if (ParamType->isMemberPointerType()) { QualType ClassType = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); NestedNameSpecifier *Qualifier = NestedNameSpecifier::Create(Context, 0, false, ClassType.getTypePtr()); CXXScopeSpec SS; SS.setScopeRep(Qualifier); ExprResult RefExpr = BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); if (RefExpr.isInvalid()) return ExprError(); RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); // We might need to perform a trailing qualification conversion, since // the element type on the parameter could be more qualified than the // element type in the expression we constructed. if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), ParamType.getUnqualifiedType())) { Expr *RefE = RefExpr.takeAs<Expr>(); ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), CK_NoOp); RefExpr = Owned(RefE); } assert(!RefExpr.isInvalid() && Context.hasSameType(((Expr*) RefExpr.get())->getType(), ParamType.getUnqualifiedType())); return move(RefExpr); } } QualType T = VD->getType().getNonReferenceType(); if (ParamType->isPointerType()) { // When the non-type template parameter is a pointer, take the // address of the declaration. ExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); if (RefExpr.isInvalid()) return ExprError(); if (T->isFunctionType() || T->isArrayType()) { // Decay functions and arrays. Expr *RefE = (Expr *)RefExpr.get(); DefaultFunctionArrayConversion(RefE); if (RefE != RefExpr.get()) { RefExpr.release(); RefExpr = Owned(RefE); } return move(RefExpr); } // Take the address of everything else return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); } // If the non-type template parameter has reference type, qualify the // resulting declaration reference with the extra qualifiers on the // type that the reference refers to. if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); return BuildDeclRefExpr(VD, T, Loc); } /// \brief Construct a new expression that refers to the given /// integral template argument with the given source-location /// information. /// /// This routine takes care of the mapping from an integral template /// argument (which may have any integral type) to the appropriate /// literal value. ExprResult Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, SourceLocation Loc) { assert(Arg.getKind() == TemplateArgument::Integral && "Operation is only value for integral template arguments"); QualType T = Arg.getIntegralType(); if (T->isCharType() || T->isWideCharType()) return Owned(new (Context) CharacterLiteral( Arg.getAsIntegral()->getZExtValue(), T->isWideCharType(), T, Loc)); if (T->isBooleanType()) return Owned(new (Context) CXXBoolLiteralExpr( Arg.getAsIntegral()->getBoolValue(), T, Loc)); return Owned(IntegerLiteral::Create(Context, *Arg.getAsIntegral(), T, Loc)); } /// \brief Determine whether the given template parameter lists are /// equivalent. /// /// \param New The new template parameter list, typically written in the /// source code as part of a new template declaration. /// /// \param Old The old template parameter list, typically found via /// name lookup of the template declared with this template parameter /// list. /// /// \param Complain If true, this routine will produce a diagnostic if /// the template parameter lists are not equivalent. /// /// \param Kind describes how we are to match the template parameter lists. /// /// \param TemplateArgLoc If this source location is valid, then we /// are actually checking the template parameter list of a template /// argument (New) against the template parameter list of its /// corresponding template template parameter (Old). We produce /// slightly different diagnostics in this scenario. /// /// \returns True if the template parameter lists are equal, false /// otherwise. bool Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, TemplateParameterList *Old, bool Complain, TemplateParameterListEqualKind Kind, SourceLocation TemplateArgLoc) { if (Old->size() != New->size()) { if (Complain) { unsigned NextDiag = diag::err_template_param_list_different_arity; if (TemplateArgLoc.isValid()) { Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); NextDiag = diag::note_template_param_list_different_arity; } Diag(New->getTemplateLoc(), NextDiag) << (New->size() > Old->size()) << (Kind != TPL_TemplateMatch) << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) << (Kind != TPL_TemplateMatch) << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); } return false; } for (TemplateParameterList::iterator OldParm = Old->begin(), OldParmEnd = Old->end(), NewParm = New->begin(); OldParm != OldParmEnd; ++OldParm, ++NewParm) { if ((*OldParm)->getKind() != (*NewParm)->getKind()) { if (Complain) { unsigned NextDiag = diag::err_template_param_different_kind; if (TemplateArgLoc.isValid()) { Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); NextDiag = diag::note_template_param_different_kind; } Diag((*NewParm)->getLocation(), NextDiag) << (Kind != TPL_TemplateMatch); Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) << (Kind != TPL_TemplateMatch); } return false; } if (TemplateTypeParmDecl *OldTTP = dyn_cast<TemplateTypeParmDecl>(*OldParm)) { // Template type parameters are equivalent if either both are template // type parameter packs or neither are (since we know we're at the same // index). TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm); if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) { // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that // allow one to match a template parameter pack in the template // parameter list of a template template parameter to one or more // template parameters in the template parameter list of the // corresponding template template argument. if (Complain) { unsigned NextDiag = diag::err_template_parameter_pack_non_pack; if (TemplateArgLoc.isValid()) { Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); NextDiag = diag::note_template_parameter_pack_non_pack; } Diag(NewTTP->getLocation(), NextDiag) << 0 << NewTTP->isParameterPack(); Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here) << 0 << OldTTP->isParameterPack(); } return false; } } else if (NonTypeTemplateParmDecl *OldNTTP = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { // The types of non-type template parameters must agree. NonTypeTemplateParmDecl *NewNTTP = cast<NonTypeTemplateParmDecl>(*NewParm); // If we are matching a template template argument to a template // template parameter and one of the non-type template parameter types // is dependent, then we must wait until template instantiation time // to actually compare the arguments. if (Kind == TPL_TemplateTemplateArgumentMatch && (OldNTTP->getType()->isDependentType() || NewNTTP->getType()->isDependentType())) continue; if (Context.getCanonicalType(OldNTTP->getType()) != Context.getCanonicalType(NewNTTP->getType())) { if (Complain) { unsigned NextDiag = diag::err_template_nontype_parm_different_type; if (TemplateArgLoc.isValid()) { Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); NextDiag = diag::note_template_nontype_parm_different_type; } Diag(NewNTTP->getLocation(), NextDiag) << NewNTTP->getType() << (Kind != TPL_TemplateMatch); Diag(OldNTTP->getLocation(), diag::note_template_nontype_parm_prev_declaration) << OldNTTP->getType(); } return false; } } else { // The template parameter lists of template template // parameters must agree. assert(isa<TemplateTemplateParmDecl>(*OldParm) && "Only template template parameters handled here"); TemplateTemplateParmDecl *OldTTP = cast<TemplateTemplateParmDecl>(*OldParm); TemplateTemplateParmDecl *NewTTP = cast<TemplateTemplateParmDecl>(*NewParm); if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), OldTTP->getTemplateParameters(), Complain, (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), TemplateArgLoc)) return false; } } return true; } /// \brief Check whether a template can be declared within this scope. /// /// If the template declaration is valid in this scope, returns /// false. Otherwise, issues a diagnostic and returns true. bool Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { // Find the nearest enclosing declaration scope. while ((S->getFlags() & Scope::DeclScope) == 0 || (S->getFlags() & Scope::TemplateParamScope) != 0) S = S->getParent(); // C++ [temp]p2: // A template-declaration can appear only as a namespace scope or // class scope declaration. DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); if (Ctx && isa<LinkageSpecDecl>(Ctx) && cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) << TemplateParams->getSourceRange(); while (Ctx && isa<LinkageSpecDecl>(Ctx)) Ctx = Ctx->getParent(); if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) return false; return Diag(TemplateParams->getTemplateLoc(), diag::err_template_outside_namespace_or_class_scope) << TemplateParams->getSourceRange(); } /// \brief Determine what kind of template specialization the given declaration /// is. static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { if (!D) return TSK_Undeclared; if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) return Record->getTemplateSpecializationKind(); if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) return Function->getTemplateSpecializationKind(); if (VarDecl *Var = dyn_cast<VarDecl>(D)) return Var->getTemplateSpecializationKind(); return TSK_Undeclared; } /// \brief Check whether a specialization is well-formed in the current /// context. /// /// This routine determines whether a template specialization can be declared /// in the current context (C++ [temp.expl.spec]p2). /// /// \param S the semantic analysis object for which this check is being /// performed. /// /// \param Specialized the entity being specialized or instantiated, which /// may be a kind of template (class template, function template, etc.) or /// a member of a class template (member function, static data member, /// member class). /// /// \param PrevDecl the previous declaration of this entity, if any. /// /// \param Loc the location of the explicit specialization or instantiation of /// this entity. /// /// \param IsPartialSpecialization whether this is a partial specialization of /// a class template. /// /// \returns true if there was an error that we cannot recover from, false /// otherwise. static bool CheckTemplateSpecializationScope(Sema &S, NamedDecl *Specialized, NamedDecl *PrevDecl, SourceLocation Loc, bool IsPartialSpecialization) { // Keep these "kind" numbers in sync with the %select statements in the // various diagnostics emitted by this routine. int EntityKind = 0; bool isTemplateSpecialization = false; if (isa<ClassTemplateDecl>(Specialized)) { EntityKind = IsPartialSpecialization? 1 : 0; isTemplateSpecialization = true; } else if (isa<FunctionTemplateDecl>(Specialized)) { EntityKind = 2; isTemplateSpecialization = true; } else if (isa<CXXMethodDecl>(Specialized)) EntityKind = 3; else if (isa<VarDecl>(Specialized)) EntityKind = 4; else if (isa<RecordDecl>(Specialized)) EntityKind = 5; else { S.Diag(Loc, diag::err_template_spec_unknown_kind); S.Diag(Specialized->getLocation(), diag::note_specialized_entity); return true; } // C++ [temp.expl.spec]p2: // An explicit specialization shall be declared in the namespace // of which the template is a member, or, for member templates, in // the namespace of which the enclosing class or enclosing class // template is a member. An explicit specialization of a member // function, member class or static data member of a class // template shall be declared in the namespace of which the class // template is a member. Such a declaration may also be a // definition. If the declaration is not a definition, the // specialization may be defined later in the name- space in which // the explicit specialization was declared, or in a namespace // that encloses the one in which the explicit specialization was // declared. if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) { S.Diag(Loc, diag::err_template_spec_decl_function_scope) << Specialized; return true; } if (S.CurContext->isRecord() && !IsPartialSpecialization) { S.Diag(Loc, diag::err_template_spec_decl_class_scope) << Specialized; return true; } // C++ [temp.class.spec]p6: // A class template partial specialization may be declared or redeclared // in any namespace scope in which its definition may be defined (14.5.1 // and 14.5.2). bool ComplainedAboutScope = false; DeclContext *SpecializedContext = Specialized->getDeclContext()->getEnclosingNamespaceContext(); DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); if ((!PrevDecl || getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ // There is no prior declaration of this entity, so this // specialization must be in the same context as the template // itself, or in the enclosing namespace set. if (!DC->InEnclosingNamespaceSetOf(SpecializedContext)) { if (isa<TranslationUnitDecl>(SpecializedContext)) S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) << EntityKind << Specialized; else if (isa<NamespaceDecl>(SpecializedContext)) S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) << EntityKind << Specialized << cast<NamedDecl>(SpecializedContext); S.Diag(Specialized->getLocation(), diag::note_specialized_entity); ComplainedAboutScope = true; } } // Make sure that this redeclaration (or definition) occurs in an enclosing // namespace. // Note that HandleDeclarator() performs this check for explicit // specializations of function templates, static data members, and member // functions, so we skip the check here for those kinds of entities. // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. // Should we refactor that check, so that it occurs later? if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || isa<FunctionDecl>(Specialized))) { if (isa<TranslationUnitDecl>(SpecializedContext)) S.Diag(Loc, diag::err_template_spec_redecl_global_scope) << EntityKind << Specialized; else if (isa<NamespaceDecl>(SpecializedContext)) S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) << EntityKind << Specialized << cast<NamedDecl>(SpecializedContext); S.Diag(Specialized->getLocation(), diag::note_specialized_entity); } // FIXME: check for specialization-after-instantiation errors and such. return false; } /// \brief Check the non-type template arguments of a class template /// partial specialization according to C++ [temp.class.spec]p9. /// /// \param TemplateParams the template parameters of the primary class /// template. /// /// \param TemplateArg the template arguments of the class template /// partial specialization. /// /// \param MirrorsPrimaryTemplate will be set true if the class /// template partial specialization arguments are identical to the /// implicit template arguments of the primary template. This is not /// necessarily an error (C++0x), and it is left to the caller to diagnose /// this condition when it is an error. /// /// \returns true if there was an error, false otherwise. bool Sema::CheckClassTemplatePartialSpecializationArgs( TemplateParameterList *TemplateParams, const TemplateArgumentListBuilder &TemplateArgs, bool &MirrorsPrimaryTemplate) { // FIXME: the interface to this function will have to change to // accommodate variadic templates. MirrorsPrimaryTemplate = true; const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { // Determine whether the template argument list of the partial // specialization is identical to the implicit argument list of // the primary template. The caller may need to diagnostic this as // an error per C++ [temp.class.spec]p9b3. if (MirrorsPrimaryTemplate) { if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != Context.getCanonicalType(ArgList[I].getAsType())) MirrorsPrimaryTemplate = false; } else if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>( TemplateParams->getParam(I))) { TemplateName Name = ArgList[I].getAsTemplate(); TemplateTemplateParmDecl *ArgDecl = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); if (!ArgDecl || ArgDecl->getIndex() != TTP->getIndex() || ArgDecl->getDepth() != TTP->getDepth()) MirrorsPrimaryTemplate = false; } } NonTypeTemplateParmDecl *Param = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); if (!Param) { continue; } Expr *ArgExpr = ArgList[I].getAsExpr(); if (!ArgExpr) { MirrorsPrimaryTemplate = false; continue; } // C++ [temp.class.spec]p8: // A non-type argument is non-specialized if it is the name of a // non-type parameter. All other non-type arguments are // specialized. // // Below, we check the two conditions that only apply to // specialized non-type arguments, so skip any non-specialized // arguments. if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { if (MirrorsPrimaryTemplate && (Param->getIndex() != NTTP->getIndex() || Param->getDepth() != NTTP->getDepth())) MirrorsPrimaryTemplate = false; continue; } // C++ [temp.class.spec]p9: // Within the argument list of a class template partial // specialization, the following restrictions apply: // -- A partially specialized non-type argument expression // shall not involve a template parameter of the partial // specialization except when the argument expression is a // simple identifier. if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { Diag(ArgExpr->getLocStart(), diag::err_dependent_non_type_arg_in_partial_spec) << ArgExpr->getSourceRange(); return true; } // -- The type of a template parameter corresponding to a // specialized non-type argument shall not be dependent on a // parameter of the specialization. if (Param->getType()->isDependentType()) { Diag(ArgExpr->getLocStart(), diag::err_dependent_typed_non_type_arg_in_partial_spec) << Param->getType() << ArgExpr->getSourceRange(); Diag(Param->getLocation(), diag::note_template_param_here); return true; } MirrorsPrimaryTemplate = false; } return false; } /// \brief Retrieve the previous declaration of the given declaration. static NamedDecl *getPreviousDecl(NamedDecl *ND) { if (VarDecl *VD = dyn_cast<VarDecl>(ND)) return VD->getPreviousDeclaration(); if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) return FD->getPreviousDeclaration(); if (TagDecl *TD = dyn_cast<TagDecl>(ND)) return TD->getPreviousDeclaration(); if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) return TD->getPreviousDeclaration(); if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) return FTD->getPreviousDeclaration(); if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) return CTD->getPreviousDeclaration(); return 0; } DeclResult Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc, CXXScopeSpec &SS, TemplateTy TemplateD, SourceLocation TemplateNameLoc, SourceLocation LAngleLoc, ASTTemplateArgsPtr TemplateArgsIn, SourceLocation RAngleLoc, AttributeList *Attr, MultiTemplateParamsArg TemplateParameterLists) { assert(TUK != TUK_Reference && "References are not specializations"); // Find the class template we're specializing TemplateName Name = TemplateD.getAsVal<TemplateName>(); ClassTemplateDecl *ClassTemplate = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); if (!ClassTemplate) { Diag(TemplateNameLoc, diag::err_not_class_template_specialization) << (Name.getAsTemplateDecl() && isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); return true; } bool isExplicitSpecialization = false; bool isPartialSpecialization = false; // Check the validity of the template headers that introduce this // template. // FIXME: We probably shouldn't complain about these headers for // friend declarations. bool Invalid = false; TemplateParameterList *TemplateParams = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, (TemplateParameterList**)TemplateParameterLists.get(), TemplateParameterLists.size(), TUK == TUK_Friend, isExplicitSpecialization, Invalid); if (Invalid) return true; unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); if (TemplateParams) --NumMatchedTemplateParamLists; if (TemplateParams && TemplateParams->size() > 0) { isPartialSpecialization = true; // C++ [temp.class.spec]p10: // The template parameter list of a specialization shall not // contain default template argument values. for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { Decl *Param = TemplateParams->getParam(I); if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { if (TTP->hasDefaultArgument()) { Diag(TTP->getDefaultArgumentLoc(), diag::err_default_arg_in_partial_spec); TTP->removeDefaultArgument(); } } else if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) { if (Expr *DefArg = NTTP->getDefaultArgument()) { Diag(NTTP->getDefaultArgumentLoc(), diag::err_default_arg_in_partial_spec) << DefArg->getSourceRange(); NTTP->removeDefaultArgument(); } } else { TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); if (TTP->hasDefaultArgument()) { Diag(TTP->getDefaultArgument().getLocation(), diag::err_default_arg_in_partial_spec) << TTP->getDefaultArgument().getSourceRange(); TTP->removeDefaultArgument(); } } } } else if (TemplateParams) { if (TUK == TUK_Friend) Diag(KWLoc, diag::err_template_spec_friend) << FixItHint::CreateRemoval( SourceRange(TemplateParams->getTemplateLoc(), TemplateParams->getRAngleLoc())) << SourceRange(LAngleLoc, RAngleLoc); else isExplicitSpecialization = true; } else if (TUK != TUK_Friend) { Diag(KWLoc, diag::err_template_spec_needs_header) << FixItHint::CreateInsertion(KWLoc, "template<> "); isExplicitSpecialization = true; } // Check that the specialization uses the same tag kind as the // original template. TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), Kind, KWLoc, *ClassTemplate->getIdentifier())) { Diag(KWLoc, diag::err_use_with_wrong_tag) << ClassTemplate << FixItHint::CreateReplacement(KWLoc, ClassTemplate->getTemplatedDecl()->getKindName()); Diag(ClassTemplate->getTemplatedDecl()->getLocation(), diag::note_previous_use); Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); } // Translate the parser's template argument list in our AST format. TemplateArgumentListInfo TemplateArgs; TemplateArgs.setLAngleLoc(LAngleLoc); TemplateArgs.setRAngleLoc(RAngleLoc); translateTemplateArguments(TemplateArgsIn, TemplateArgs); // Check that the template argument list is well-formed for this // template. TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), TemplateArgs.size()); if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, TemplateArgs, false, Converted)) return true; assert((Converted.structuredSize() == ClassTemplate->getTemplateParameters()->size()) && "Converted template argument list is too short!"); // Find the class template (partial) specialization declaration that // corresponds to these arguments. if (isPartialSpecialization) { bool MirrorsPrimaryTemplate; if (CheckClassTemplatePartialSpecializationArgs( ClassTemplate->getTemplateParameters(), Converted, MirrorsPrimaryTemplate)) return true; if (MirrorsPrimaryTemplate) { // C++ [temp.class.spec]p9b3: // // -- The argument list of the specialization shall not be identical // to the implicit argument list of the primary template. Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) << (TUK == TUK_Definition) << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, ClassTemplate->getIdentifier(), TemplateNameLoc, Attr, TemplateParams, AS_none); } // FIXME: Diagnose friend partial specializations if (!Name.isDependent() && !TemplateSpecializationType::anyDependentTemplateArguments( TemplateArgs.getArgumentArray(), TemplateArgs.size())) { Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) << ClassTemplate->getDeclName(); isPartialSpecialization = false; } } void *InsertPos = 0; ClassTemplateSpecializationDecl *PrevDecl = 0; if (isPartialSpecialization) // FIXME: Template parameter list matters, too PrevDecl = ClassTemplate->findPartialSpecialization(Converted.getFlatArguments(), Converted.flatSize(), InsertPos); else PrevDecl = ClassTemplate->findSpecialization(Converted.getFlatArguments(), Converted.flatSize(), InsertPos); ClassTemplateSpecializationDecl *Specialization = 0; // Check whether we can declare a class template specialization in // the current scope. if (TUK != TUK_Friend && CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, TemplateNameLoc, isPartialSpecialization)) return true; // The canonical type QualType CanonType; if (PrevDecl && (PrevDecl->getSpecializationKind() == TSK_Undeclared || TUK == TUK_Friend)) { // Since the only prior class template specialization with these // arguments was referenced but not declared, or we're only // referencing this specialization as a friend, reuse that // declaration node as our own, updating its source location to // reflect our new declaration. Specialization = PrevDecl; Specialization->setLocation(TemplateNameLoc); PrevDecl = 0; CanonType = Context.getTypeDeclType(Specialization); } else if (isPartialSpecialization) { // Build the canonical type that describes the converted template // arguments of the class template partial specialization. TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); CanonType = Context.getTemplateSpecializationType(CanonTemplate, Converted.getFlatArguments(), Converted.flatSize()); // Create a new class template partial specialization declaration node. ClassTemplatePartialSpecializationDecl *PrevPartial = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() : ClassTemplate->getNextPartialSpecSequenceNumber(); ClassTemplatePartialSpecializationDecl *Partial = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, ClassTemplate->getDeclContext(), TemplateNameLoc, TemplateParams, ClassTemplate, Converted, TemplateArgs, CanonType, PrevPartial, SequenceNumber); SetNestedNameSpecifier(Partial, SS); if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { Partial->setTemplateParameterListsInfo(Context, NumMatchedTemplateParamLists, (TemplateParameterList**) TemplateParameterLists.release()); } if (!PrevPartial) ClassTemplate->AddPartialSpecialization(Partial, InsertPos); Specialization = Partial; // If we are providing an explicit specialization of a member class // template specialization, make a note of that. if (PrevPartial && PrevPartial->getInstantiatedFromMember()) PrevPartial->setMemberSpecialization(); // Check that all of the template parameters of the class template // partial specialization are deducible from the template // arguments. If not, this class template partial specialization // will never be used. llvm::SmallVector<bool, 8> DeducibleParams; DeducibleParams.resize(TemplateParams->size()); MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, TemplateParams->getDepth(), DeducibleParams); unsigned NumNonDeducible = 0; for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) if (!DeducibleParams[I]) ++NumNonDeducible; if (NumNonDeducible) { Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) << (NumNonDeducible > 1) << SourceRange(TemplateNameLoc, RAngleLoc); for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { if (!DeducibleParams[I]) { NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); if (Param->getDeclName()) Diag(Param->getLocation(), diag::note_partial_spec_unused_parameter) << Param->getDeclName(); else Diag(Param->getLocation(), diag::note_partial_spec_unused_parameter) << "<anonymous>"; } } } } else { // Create a new class template specialization declaration node for // this explicit specialization or friend declaration. Specialization = ClassTemplateSpecializationDecl::Create(Context, Kind, ClassTemplate->getDeclContext(), TemplateNameLoc, ClassTemplate, Converted, PrevDecl); SetNestedNameSpecifier(Specialization, SS); if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { Specialization->setTemplateParameterListsInfo(Context, NumMatchedTemplateParamLists, (TemplateParameterList**) TemplateParameterLists.release()); } if (!PrevDecl) ClassTemplate->AddSpecialization(Specialization, InsertPos); CanonType = Context.getTypeDeclType(Specialization); } // C++ [temp.expl.spec]p6: // If a template, a member template or the member of a class template is // explicitly specialized then that specialization shall be declared // before the first use of that specialization that would cause an implicit // instantiation to take place, in every translation unit in which such a // use occurs; no diagnostic is required. if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { bool Okay = false; for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { // Is there any previous explicit specialization declaration? if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { Okay = true; break; } } if (!Okay) { SourceRange Range(TemplateNameLoc, RAngleLoc); Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) << Context.getTypeDeclType(Specialization) << Range; Diag(PrevDecl->getPointOfInstantiation(), diag::note_instantiation_required_here) << (PrevDecl->getTemplateSpecializationKind() != TSK_ImplicitInstantiation); return true; } } // If this is not a friend, note that this is an explicit specialization. if (TUK != TUK_Friend) Specialization->setSpecializationKind(TSK_ExplicitSpecialization); // Check that this isn't a redefinition of this specialization. if (TUK == TUK_Definition) { if (RecordDecl *Def = Specialization->getDefinition()) { SourceRange Range(TemplateNameLoc, RAngleLoc); Diag(TemplateNameLoc, diag::err_redefinition) << Context.getTypeDeclType(Specialization) << Range; Diag(Def->getLocation(), diag::note_previous_definition); Specialization->setInvalidDecl(); return true; } } // Build the fully-sugared type for this class template // specialization as the user wrote in the specialization // itself. This means that we'll pretty-print the type retrieved // from the specialization's declaration the way that the user // actually wrote the specialization, rather than formatting the // name based on the "canonical" representation used to store the // template arguments in the specialization. TypeSourceInfo *WrittenTy = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, TemplateArgs, CanonType); if (TUK != TUK_Friend) { Specialization->setTypeAsWritten(WrittenTy); if (TemplateParams) Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc()); } TemplateArgsIn.release(); // C++ [temp.expl.spec]p9: // A template explicit specialization is in the scope of the // namespace in which the template was defined. // // We actually implement this paragraph where we set the semantic // context (in the creation of the ClassTemplateSpecializationDecl), // but we also maintain the lexical context where the actual // definition occurs. Specialization->setLexicalDeclContext(CurContext); // We may be starting the definition of this specialization. if (TUK == TUK_Definition) Specialization->startDefinition(); if (TUK == TUK_Friend) { FriendDecl *Friend = FriendDecl::Create(Context, CurContext, TemplateNameLoc, WrittenTy, /*FIXME:*/KWLoc); Friend->setAccess(AS_public); CurContext->addDecl(Friend); } else { // Add the specialization into its lexical context, so that it can // be seen when iterating through the list of declarations in that // context. However, specializations are not found by name lookup. CurContext->addDecl(Specialization); } return Specialization; } Decl *Sema::ActOnTemplateDeclarator(Scope *S, MultiTemplateParamsArg TemplateParameterLists, Declarator &D) { return HandleDeclarator(S, D, move(TemplateParameterLists), false); } Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, MultiTemplateParamsArg TemplateParameterLists, Declarator &D) { assert(getCurFunctionDecl() == 0 && "Function parsing confused"); assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && "Not a function declarator!"); DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; if (FTI.hasPrototype) { // FIXME: Diagnose arguments without names in C. } Scope *ParentScope = FnBodyScope->getParent(); Decl *DP = HandleDeclarator(ParentScope, D, move(TemplateParameterLists), /*IsFunctionDefinition=*/true); if (FunctionTemplateDecl *FunctionTemplate = dyn_cast_or_null<FunctionTemplateDecl>(DP)) return ActOnStartOfFunctionDef(FnBodyScope, FunctionTemplate->getTemplatedDecl()); if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP)) return ActOnStartOfFunctionDef(FnBodyScope, Function); return 0; } /// \brief Strips various properties off an implicit instantiation /// that has just been explicitly specialized. static void StripImplicitInstantiation(NamedDecl *D) { D->dropAttrs(); if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { FD->setInlineSpecified(false); } } /// \brief Diagnose cases where we have an explicit template specialization /// before/after an explicit template instantiation, producing diagnostics /// for those cases where they are required and determining whether the /// new specialization/instantiation will have any effect. /// /// \param NewLoc the location of the new explicit specialization or /// instantiation. /// /// \param NewTSK the kind of the new explicit specialization or instantiation. /// /// \param PrevDecl the previous declaration of the entity. /// /// \param PrevTSK the kind of the old explicit specialization or instantiatin. /// /// \param PrevPointOfInstantiation if valid, indicates where the previus /// declaration was instantiated (either implicitly or explicitly). /// /// \param HasNoEffect will be set to true to indicate that the new /// specialization or instantiation has no effect and should be ignored. /// /// \returns true if there was an error that should prevent the introduction of /// the new declaration into the AST, false otherwise. bool Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, TemplateSpecializationKind NewTSK, NamedDecl *PrevDecl, TemplateSpecializationKind PrevTSK, SourceLocation PrevPointOfInstantiation, bool &HasNoEffect) { HasNoEffect = false; switch (NewTSK) { case TSK_Undeclared: case TSK_ImplicitInstantiation: assert(false && "Don't check implicit instantiations here"); return false; case TSK_ExplicitSpecialization: switch (PrevTSK) { case TSK_Undeclared: case TSK_ExplicitSpecialization: // Okay, we're just specializing something that is either already // explicitly specialized or has merely been mentioned without any // instantiation. return false; case TSK_ImplicitInstantiation: if (PrevPointOfInstantiation.isInvalid()) { // The declaration itself has not actually been instantiated, so it is // still okay to specialize it. StripImplicitInstantiation(PrevDecl); return false; } // Fall through case TSK_ExplicitInstantiationDeclaration: case TSK_ExplicitInstantiationDefinition: assert((PrevTSK == TSK_ImplicitInstantiation || PrevPointOfInstantiation.isValid()) && "Explicit instantiation without point of instantiation?"); // C++ [temp.expl.spec]p6: // If a template, a member template or the member of a class template // is explicitly specialized then that specialization shall be declared // before the first use of that specialization that would cause an // implicit instantiation to take place, in every translation unit in // which such a use occurs; no diagnostic is required. for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { // Is there any previous explicit specialization declaration? if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) return false; } Diag(NewLoc, diag::err_specialization_after_instantiation) << PrevDecl; Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) << (PrevTSK != TSK_ImplicitInstantiation); return true; } break; case TSK_ExplicitInstantiationDeclaration: switch (PrevTSK) { case TSK_ExplicitInstantiationDeclaration: // This explicit instantiation declaration is redundant (that's okay). HasNoEffect = true; return false; case TSK_Undeclared: case TSK_ImplicitInstantiation: // We're explicitly instantiating something that may have already been // implicitly instantiated; that's fine. return false; case TSK_ExplicitSpecialization: // C++0x [temp.explicit]p4: // For a given set of template parameters, if an explicit instantiation // of a template appears after a declaration of an explicit // specialization for that template, the explicit instantiation has no // effect. HasNoEffect = true; return false; case TSK_ExplicitInstantiationDefinition: // C++0x [temp.explicit]p10: // If an entity is the subject of both an explicit instantiation // declaration and an explicit instantiation definition in the same // translation unit, the definition shall follow the declaration. Diag(NewLoc, diag::err_explicit_instantiation_declaration_after_definition); Diag(PrevPointOfInstantiation, diag::note_explicit_instantiation_definition_here); assert(PrevPointOfInstantiation.isValid() && "Explicit instantiation without point of instantiation?"); HasNoEffect = true; return false; } break; case TSK_ExplicitInstantiationDefinition: switch (PrevTSK) { case TSK_Undeclared: case TSK_ImplicitInstantiation: // We're explicitly instantiating something that may have already been // implicitly instantiated; that's fine. return false; case TSK_ExplicitSpecialization: // C++ DR 259, C++0x [temp.explicit]p4: // For a given set of template parameters, if an explicit // instantiation of a template appears after a declaration of // an explicit specialization for that template, the explicit // instantiation has no effect. // // In C++98/03 mode, we only give an extension warning here, because it // is not harmful to try to explicitly instantiate something that // has been explicitly specialized. if (!getLangOptions().CPlusPlus0x) { Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) << PrevDecl; Diag(PrevDecl->getLocation(), diag::note_previous_template_specialization); } HasNoEffect = true; return false; case TSK_ExplicitInstantiationDeclaration: // We're explicity instantiating a definition for something for which we // were previously asked to suppress instantiations. That's fine. return false; case TSK_ExplicitInstantiationDefinition: // C++0x [temp.spec]p5: // For a given template and a given set of template-arguments, // - an explicit instantiation definition shall appear at most once // in a program, Diag(NewLoc, diag::err_explicit_instantiation_duplicate) << PrevDecl; Diag(PrevPointOfInstantiation, diag::note_previous_explicit_instantiation); HasNoEffect = true; return false; } break; } assert(false && "Missing specialization/instantiation case?"); return false; } /// \brief Perform semantic analysis for the given dependent function /// template specialization. The only possible way to get a dependent /// function template specialization is with a friend declaration, /// like so: /// /// template <class T> void foo(T); /// template <class T> class A { /// friend void foo<>(T); /// }; /// /// There really isn't any useful analysis we can do here, so we /// just store the information. bool Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, const TemplateArgumentListInfo &ExplicitTemplateArgs, LookupResult &Previous) { // Remove anything from Previous that isn't a function template in // the correct context. DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); LookupResult::Filter F = Previous.makeFilter(); while (F.hasNext()) { NamedDecl *D = F.next()->getUnderlyingDecl(); if (!isa<FunctionTemplateDecl>(D) || !FDLookupContext->InEnclosingNamespaceSetOf( D->getDeclContext()->getRedeclContext())) F.erase(); } F.done(); // Should this be diagnosed here? if (Previous.empty()) return true; FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), ExplicitTemplateArgs); return false; } /// \brief Perform semantic analysis for the given function template /// specialization. /// /// This routine performs all of the semantic analysis required for an /// explicit function template specialization. On successful completion, /// the function declaration \p FD will become a function template /// specialization. /// /// \param FD the function declaration, which will be updated to become a /// function template specialization. /// /// \param ExplicitTemplateArgs the explicitly-provided template arguments, /// if any. Note that this may be valid info even when 0 arguments are /// explicitly provided as in, e.g., \c void sort<>(char*, char*); /// as it anyway contains info on the angle brackets locations. /// /// \param PrevDecl the set of declarations that may be specialized by /// this function specialization. bool Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, const TemplateArgumentListInfo *ExplicitTemplateArgs, LookupResult &Previous) { // The set of function template specializations that could match this // explicit function template specialization. UnresolvedSet<8> Candidates; DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); I != E; ++I) { NamedDecl *Ovl = (*I)->getUnderlyingDecl(); if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { // Only consider templates found within the same semantic lookup scope as // FD. if (!FDLookupContext->InEnclosingNamespaceSetOf( Ovl->getDeclContext()->getRedeclContext())) continue; // C++ [temp.expl.spec]p11: // A trailing template-argument can be left unspecified in the // template-id naming an explicit function template specialization // provided it can be deduced from the function argument type. // Perform template argument deduction to determine whether we may be // specializing this template. // FIXME: It is somewhat wasteful to build TemplateDeductionInfo Info(Context, FD->getLocation()); FunctionDecl *Specialization = 0; if (TemplateDeductionResult TDK = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, FD->getType(), Specialization, Info)) { // FIXME: Template argument deduction failed; record why it failed, so // that we can provide nifty diagnostics. (void)TDK; continue; } // Record this candidate. Candidates.addDecl(Specialization, I.getAccess()); } } // Find the most specialized function template. UnresolvedSetIterator Result = getMostSpecialized(Candidates.begin(), Candidates.end(), TPOC_Other, FD->getLocation(), PDiag(diag::err_function_template_spec_no_match) << FD->getDeclName(), PDiag(diag::err_function_template_spec_ambiguous) << FD->getDeclName() << (ExplicitTemplateArgs != 0), PDiag(diag::note_function_template_spec_matched)); if (Result == Candidates.end()) return true; // Ignore access information; it doesn't figure into redeclaration checking. FunctionDecl *Specialization = cast<FunctionDecl>(*Result); Specialization->setLocation(FD->getLocation()); // FIXME: Check if the prior specialization has a point of instantiation. // If so, we have run afoul of . // If this is a friend declaration, then we're not really declaring // an explicit specialization. bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); // Check the scope of this explicit specialization. if (!isFriend && CheckTemplateSpecializationScope(*this, Specialization->getPrimaryTemplate(), Specialization, FD->getLocation(), false)) return true; // C++ [temp.expl.spec]p6: // If a template, a member template or the member of a class template is // explicitly specialized then that specialization shall be declared // before the first use of that specialization that would cause an implicit // instantiation to take place, in every translation unit in which such a // use occurs; no diagnostic is required. FunctionTemplateSpecializationInfo *SpecInfo = Specialization->getTemplateSpecializationInfo(); assert(SpecInfo && "Function template specialization info missing?"); bool HasNoEffect = false; if (!isFriend && CheckSpecializationInstantiationRedecl(FD->getLocation(), TSK_ExplicitSpecialization, Specialization, SpecInfo->getTemplateSpecializationKind(), SpecInfo->getPointOfInstantiation(), HasNoEffect)) return true; // Mark the prior declaration as an explicit specialization, so that later // clients know that this is an explicit specialization. if (!isFriend) { SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); MarkUnusedFileScopedDecl(Specialization); } // Turn the given function declaration into a function template // specialization, with the template arguments from the previous // specialization. // Take copies of (semantic and syntactic) template argument lists. const TemplateArgumentList* TemplArgs = new (Context) TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0; FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), TemplArgs, /*InsertPos=*/0, SpecInfo->getTemplateSpecializationKind(), TemplArgsAsWritten); // The "previous declaration" for this function template specialization is // the prior function template specialization. Previous.clear(); Previous.addDecl(Specialization); return false; } /// \brief Perform semantic analysis for the given non-template member /// specialization. /// /// This routine performs all of the semantic analysis required for an /// explicit member function specialization. On successful completion, /// the function declaration \p FD will become a member function /// specialization. /// /// \param Member the member declaration, which will be updated to become a /// specialization. /// /// \param Previous the set of declarations, one of which may be specialized /// by this function specialization; the set will be modified to contain the /// redeclared member. bool Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); // Try to find the member we are instantiating. NamedDecl *Instantiation = 0; NamedDecl *InstantiatedFrom = 0; MemberSpecializationInfo *MSInfo = 0; if (Previous.empty()) { // Nowhere to look anyway. } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); I != E; ++I) { NamedDecl *D = (*I)->getUnderlyingDecl(); if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { if (Context.hasSameType(Function->getType(), Method->getType())) { Instantiation = Method; InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); MSInfo = Method->getMemberSpecializationInfo(); break; } } } } else if (isa<VarDecl>(Member)) { VarDecl *PrevVar; if (Previous.isSingleResult() && (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) if (PrevVar->isStaticDataMember()) { Instantiation = PrevVar; InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); MSInfo = PrevVar->getMemberSpecializationInfo(); } } else if (isa<RecordDecl>(Member)) { CXXRecordDecl *PrevRecord; if (Previous.isSingleResult() && (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { Instantiation = PrevRecord; InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); MSInfo = PrevRecord->getMemberSpecializationInfo(); } } if (!Instantiation) { // There is no previous declaration that matches. Since member // specializations are always out-of-line, the caller will complain about // this mismatch later. return false; } // If this is a friend, just bail out here before we start turning // things into explicit specializations. if (Member->getFriendObjectKind() != Decl::FOK_None) { // Preserve instantiation information. if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( cast<CXXMethodDecl>(InstantiatedFrom), cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( cast<CXXRecordDecl>(InstantiatedFrom), cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); } Previous.clear(); Previous.addDecl(Instantiation); return false; } // Make sure that this is a specialization of a member. if (!InstantiatedFrom) { Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) << Member; Diag(Instantiation->getLocation(), diag::note_specialized_decl); return true; } // C++ [temp.expl.spec]p6: // If a template, a member template or the member of a class template is // explicitly specialized then that spe- cialization shall be declared // before the first use of that specialization that would cause an implicit // instantiation to take place, in every translation unit in which such a // use occurs; no diagnostic is required. assert(MSInfo && "Member specialization info missing?"); bool HasNoEffect = false; if (CheckSpecializationInstantiationRedecl(Member->getLocation(), TSK_ExplicitSpecialization, Instantiation, MSInfo->getTemplateSpecializationKind(), MSInfo->getPointOfInstantiation(), HasNoEffect)) return true; // Check the scope of this explicit specialization. if (CheckTemplateSpecializationScope(*this, InstantiatedFrom, Instantiation, Member->getLocation(), false)) return true; // Note that this is an explicit instantiation of a member. // the original declaration to note that it is an explicit specialization // (if it was previously an implicit instantiation). This latter step // makes bookkeeping easier. if (isa<FunctionDecl>(Member)) { FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); if (InstantiationFunction->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) { InstantiationFunction->setTemplateSpecializationKind( TSK_ExplicitSpecialization); InstantiationFunction->setLocation(Member->getLocation()); } cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( cast<CXXMethodDecl>(InstantiatedFrom), TSK_ExplicitSpecialization); MarkUnusedFileScopedDecl(InstantiationFunction); } else if (isa<VarDecl>(Member)) { VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); if (InstantiationVar->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) { InstantiationVar->setTemplateSpecializationKind( TSK_ExplicitSpecialization); InstantiationVar->setLocation(Member->getLocation()); } Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), cast<VarDecl>(InstantiatedFrom), TSK_ExplicitSpecialization); MarkUnusedFileScopedDecl(InstantiationVar); } else { assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); if (InstantiationClass->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) { InstantiationClass->setTemplateSpecializationKind( TSK_ExplicitSpecialization); InstantiationClass->setLocation(Member->getLocation()); } cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( cast<CXXRecordDecl>(InstantiatedFrom), TSK_ExplicitSpecialization); } // Save the caller the trouble of having to figure out which declaration // this specialization matches. Previous.clear(); Previous.addDecl(Instantiation); return false; } /// \brief Check the scope of an explicit instantiation. /// /// \returns true if a serious error occurs, false otherwise. static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, SourceLocation InstLoc, bool WasQualifiedName) { DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext(); DeclContext *CurContext = S.CurContext->getRedeclContext(); if (CurContext->isRecord()) { S.Diag(InstLoc, diag::err_explicit_instantiation_in_class) << D; return true; } // C++0x [temp.explicit]p2: // An explicit instantiation shall appear in an enclosing namespace of its // template. // // This is DR275, which we do not retroactively apply to C++98/03. if (S.getLangOptions().CPlusPlus0x && !CurContext->Encloses(OrigContext)) { if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext)) S.Diag(InstLoc, S.getLangOptions().CPlusPlus0x? diag::err_explicit_instantiation_out_of_scope : diag::warn_explicit_instantiation_out_of_scope_0x) << D << NS; else S.Diag(InstLoc, S.getLangOptions().CPlusPlus0x? diag::err_explicit_instantiation_must_be_global : diag::warn_explicit_instantiation_out_of_scope_0x) << D; S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); return false; } // C++0x [temp.explicit]p2: // If the name declared in the explicit instantiation is an unqualified // name, the explicit instantiation shall appear in the namespace where // its template is declared or, if that namespace is inline (7.3.1), any // namespace from its enclosing namespace set. if (WasQualifiedName) return false; if (CurContext->InEnclosingNamespaceSetOf(OrigContext)) return false; S.Diag(InstLoc, S.getLangOptions().CPlusPlus0x? diag::err_explicit_instantiation_unqualified_wrong_namespace : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) << D << OrigContext; S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); return false; } /// \brief Determine whether the given scope specifier has a template-id in it. static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { if (!SS.isSet()) return false; // C++0x [temp.explicit]p2: // If the explicit instantiation is for a member function, a member class // or a static data member of a class template specialization, the name of // the class template specialization in the qualified-id for the member // name shall be a simple-template-id. // // C++98 has the same restriction, just worded differently. for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); NNS; NNS = NNS->getPrefix()) if (Type *T = NNS->getAsType()) if (isa<TemplateSpecializationType>(T)) return true; return false; } // Explicit instantiation of a class template specialization DeclResult Sema::ActOnExplicitInstantiation(Scope *S, SourceLocation ExternLoc, SourceLocation TemplateLoc, unsigned TagSpec, SourceLocation KWLoc, const CXXScopeSpec &SS, TemplateTy TemplateD, SourceLocation TemplateNameLoc, SourceLocation LAngleLoc, ASTTemplateArgsPtr TemplateArgsIn, SourceLocation RAngleLoc, AttributeList *Attr) { // Find the class template we're specializing TemplateName Name = TemplateD.getAsVal<TemplateName>(); ClassTemplateDecl *ClassTemplate = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); // Check that the specialization uses the same tag kind as the // original template. TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); assert(Kind != TTK_Enum && "Invalid enum tag in class template explicit instantiation!"); if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), Kind, KWLoc, *ClassTemplate->getIdentifier())) { Diag(KWLoc, diag::err_use_with_wrong_tag) << ClassTemplate << FixItHint::CreateReplacement(KWLoc, ClassTemplate->getTemplatedDecl()->getKindName()); Diag(ClassTemplate->getTemplatedDecl()->getLocation(), diag::note_previous_use); Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); } // C++0x [temp.explicit]p2: // There are two forms of explicit instantiation: an explicit instantiation // definition and an explicit instantiation declaration. An explicit // instantiation declaration begins with the extern keyword. [...] TemplateSpecializationKind TSK = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition : TSK_ExplicitInstantiationDeclaration; // Translate the parser's template argument list in our AST format. TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); translateTemplateArguments(TemplateArgsIn, TemplateArgs); // Check that the template argument list is well-formed for this // template. TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), TemplateArgs.size()); if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, TemplateArgs, false, Converted)) return true; assert((Converted.structuredSize() == ClassTemplate->getTemplateParameters()->size()) && "Converted template argument list is too short!"); // Find the class template specialization declaration that // corresponds to these arguments. void *InsertPos = 0; ClassTemplateSpecializationDecl *PrevDecl = ClassTemplate->findSpecialization(Converted.getFlatArguments(), Converted.flatSize(), InsertPos); TemplateSpecializationKind PrevDecl_TSK = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; // C++0x [temp.explicit]p2: // [...] An explicit instantiation shall appear in an enclosing // namespace of its template. [...] // // This is C++ DR 275. if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, SS.isSet())) return true; ClassTemplateSpecializationDecl *Specialization = 0; bool ReusedDecl = false; bool HasNoEffect = false; if (PrevDecl) { if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, PrevDecl, PrevDecl_TSK, PrevDecl->getPointOfInstantiation(), HasNoEffect)) return PrevDecl; // Even though HasNoEffect == true means that this explicit instantiation // has no effect on semantics, we go on to put its syntax in the AST. if (PrevDecl_TSK == TSK_ImplicitInstantiation || PrevDecl_TSK == TSK_Undeclared) { // Since the only prior class template specialization with these // arguments was referenced but not declared, reuse that // declaration node as our own, updating the source location // for the template name to reflect our new declaration. // (Other source locations will be updated later.) Specialization = PrevDecl; Specialization->setLocation(TemplateNameLoc); PrevDecl = 0; ReusedDecl = true; } } if (!Specialization) { // Create a new class template specialization declaration node for // this explicit specialization. Specialization = ClassTemplateSpecializationDecl::Create(Context, Kind, ClassTemplate->getDeclContext(), TemplateNameLoc, ClassTemplate, Converted, PrevDecl); SetNestedNameSpecifier(Specialization, SS); if (!HasNoEffect && !PrevDecl) { // Insert the new specialization. ClassTemplate->AddSpecialization(Specialization, InsertPos); } } // Build the fully-sugared type for this explicit instantiation as // the user wrote in the explicit instantiation itself. This means // that we'll pretty-print the type retrieved from the // specialization's declaration the way that the user actually wrote // the explicit instantiation, rather than formatting the name based // on the "canonical" representation used to store the template // arguments in the specialization. TypeSourceInfo *WrittenTy = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, TemplateArgs, Context.getTypeDeclType(Specialization)); Specialization->setTypeAsWritten(WrittenTy); TemplateArgsIn.release(); // Set source locations for keywords. Specialization->setExternLoc(ExternLoc); Specialization->setTemplateKeywordLoc(TemplateLoc); // Add the explicit instantiation into its lexical context. However, // since explicit instantiations are never found by name lookup, we // just put it into the declaration context directly. Specialization->setLexicalDeclContext(CurContext); CurContext->addDecl(Specialization); // Syntax is now OK, so return if it has no other effect on semantics. if (HasNoEffect) { // Set the template specialization kind. Specialization->setTemplateSpecializationKind(TSK); return Specialization; } // C++ [temp.explicit]p3: // A definition of a class template or class member template // shall be in scope at the point of the explicit instantiation of // the class template or class member template. // // This check comes when we actually try to perform the // instantiation. ClassTemplateSpecializationDecl *Def = cast_or_null<ClassTemplateSpecializationDecl>( Specialization->getDefinition()); if (!Def) InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); else if (TSK == TSK_ExplicitInstantiationDefinition) { MarkVTableUsed(TemplateNameLoc, Specialization, true); Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); } // Instantiate the members of this class template specialization. Def = cast_or_null<ClassTemplateSpecializationDecl>( Specialization->getDefinition()); if (Def) { TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); // Fix a TSK_ExplicitInstantiationDeclaration followed by a // TSK_ExplicitInstantiationDefinition if (Old_TSK == TSK_ExplicitInstantiationDeclaration && TSK == TSK_ExplicitInstantiationDefinition) Def->setTemplateSpecializationKind(TSK); InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); } // Set the template specialization kind. Specialization->setTemplateSpecializationKind(TSK); return Specialization; } // Explicit instantiation of a member class of a class template. DeclResult Sema::ActOnExplicitInstantiation(Scope *S, SourceLocation ExternLoc, SourceLocation TemplateLoc, unsigned TagSpec, SourceLocation KWLoc, CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc, AttributeList *Attr) { bool Owned = false; bool IsDependent = false; Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference, KWLoc, SS, Name, NameLoc, Attr, AS_none, MultiTemplateParamsArg(*this, 0, 0), Owned, IsDependent); assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); if (!TagD) return true; TagDecl *Tag = cast<TagDecl>(TagD); if (Tag->isEnum()) { Diag(TemplateLoc, diag::err_explicit_instantiation_enum) << Context.getTypeDeclType(Tag); return true; } if (Tag->isInvalidDecl()) return true; CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); if (!Pattern) { Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) << Context.getTypeDeclType(Record); Diag(Record->getLocation(), diag::note_nontemplate_decl_here); return true; } // C++0x [temp.explicit]p2: // If the explicit instantiation is for a class or member class, the // elaborated-type-specifier in the declaration shall include a // simple-template-id. // // C++98 has the same restriction, just worded differently. if (!ScopeSpecifierHasTemplateId(SS)) Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id) << Record << SS.getRange(); // C++0x [temp.explicit]p2: // There are two forms of explicit instantiation: an explicit instantiation // definition and an explicit instantiation declaration. An explicit // instantiation declaration begins with the extern keyword. [...] TemplateSpecializationKind TSK = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition : TSK_ExplicitInstantiationDeclaration; // C++0x [temp.explicit]p2: // [...] An explicit instantiation shall appear in an enclosing // namespace of its template. [...] // // This is C++ DR 275. CheckExplicitInstantiationScope(*this, Record, NameLoc, true); // Verify that it is okay to explicitly instantiate here. CXXRecordDecl *PrevDecl = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); if (!PrevDecl && Record->getDefinition()) PrevDecl = Record; if (PrevDecl) { MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); bool HasNoEffect = false; assert(MSInfo && "No member specialization information?"); if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, PrevDecl, MSInfo->getTemplateSpecializationKind(), MSInfo->getPointOfInstantiation(), HasNoEffect)) return true; if (HasNoEffect) return TagD; } CXXRecordDecl *RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); if (!RecordDef) { // C++ [temp.explicit]p3: // A definition of a member class of a class template shall be in scope // at the point of an explicit instantiation of the member class. CXXRecordDecl *Def = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); if (!Def) { Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) << 0 << Record->getDeclName() << Record->getDeclContext(); Diag(Pattern->getLocation(), diag::note_forward_declaration) << Pattern; return true; } else { if (InstantiateClass(NameLoc, Record, Def, getTemplateInstantiationArgs(Record), TSK)) return true; RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); if (!RecordDef) return true; } } // Instantiate all of the members of the class. InstantiateClassMembers(NameLoc, RecordDef, getTemplateInstantiationArgs(Record), TSK); if (TSK == TSK_ExplicitInstantiationDefinition) MarkVTableUsed(NameLoc, RecordDef, true); // FIXME: We don't have any representation for explicit instantiations of // member classes. Such a representation is not needed for compilation, but it // should be available for clients that want to see all of the declarations in // the source code. return TagD; } DeclResult Sema::ActOnExplicitInstantiation(Scope *S, SourceLocation ExternLoc, SourceLocation TemplateLoc, Declarator &D) { // Explicit instantiations always require a name. // TODO: check if/when DNInfo should replace Name. DeclarationNameInfo NameInfo = GetNameForDeclarator(D); DeclarationName Name = NameInfo.getName(); if (!Name) { if (!D.isInvalidType()) Diag(D.getDeclSpec().getSourceRange().getBegin(), diag::err_explicit_instantiation_requires_name) << D.getDeclSpec().getSourceRange() << D.getSourceRange(); return true; } // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. while ((S->getFlags() & Scope::DeclScope) == 0 || (S->getFlags() & Scope::TemplateParamScope) != 0) S = S->getParent(); // Determine the type of the declaration. TypeSourceInfo *T = GetTypeForDeclarator(D, S); QualType R = T->getType(); if (R.isNull()) return true; if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { // Cannot explicitly instantiate a typedef. Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) << Name; return true; } // C++0x [temp.explicit]p1: // [...] An explicit instantiation of a function template shall not use the // inline or constexpr specifiers. // Presumably, this also applies to member functions of class templates as // well. if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_explicit_instantiation_inline) <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); // FIXME: check for constexpr specifier. // C++0x [temp.explicit]p2: // There are two forms of explicit instantiation: an explicit instantiation // definition and an explicit instantiation declaration. An explicit // instantiation declaration begins with the extern keyword. [...] TemplateSpecializationKind TSK = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition : TSK_ExplicitInstantiationDeclaration; LookupResult Previous(*this, NameInfo, LookupOrdinaryName); LookupParsedName(Previous, S, &D.getCXXScopeSpec()); if (!R->isFunctionType()) { // C++ [temp.explicit]p1: // A [...] static data member of a class template can be explicitly // instantiated from the member definition associated with its class // template. if (Previous.isAmbiguous()) return true; VarDecl *Prev = Previous.getAsSingle<VarDecl>(); if (!Prev || !Prev->isStaticDataMember()) { // We expect to see a data data member here. Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) << Name; for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); P != PEnd; ++P) Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); return true; } if (!Prev->getInstantiatedFromStaticDataMember()) { // FIXME: Check for explicit specialization? Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_data_member_not_instantiated) << Prev; Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); // FIXME: Can we provide a note showing where this was declared? return true; } // C++0x [temp.explicit]p2: // If the explicit instantiation is for a member function, a member class // or a static data member of a class template specialization, the name of // the class template specialization in the qualified-id for the member // name shall be a simple-template-id. // // C++98 has the same restriction, just worded differently. if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) Diag(D.getIdentifierLoc(), diag::ext_explicit_instantiation_without_qualified_id) << Prev << D.getCXXScopeSpec().getRange(); // Check the scope of this explicit instantiation. CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); // Verify that it is okay to explicitly instantiate here. MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); assert(MSInfo && "Missing static data member specialization info?"); bool HasNoEffect = false; if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, MSInfo->getTemplateSpecializationKind(), MSInfo->getPointOfInstantiation(), HasNoEffect)) return true; if (HasNoEffect) return (Decl*) 0; // Instantiate static data member. Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); if (TSK == TSK_ExplicitInstantiationDefinition) InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev); // FIXME: Create an ExplicitInstantiation node? return (Decl*) 0; } // If the declarator is a template-id, translate the parser's template // argument list into our AST format. bool HasExplicitTemplateArgs = false; TemplateArgumentListInfo TemplateArgs; if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { TemplateIdAnnotation *TemplateId = D.getName().TemplateId; TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); ASTTemplateArgsPtr TemplateArgsPtr(*this, TemplateId->getTemplateArgs(), TemplateId->NumArgs); translateTemplateArguments(TemplateArgsPtr, TemplateArgs); HasExplicitTemplateArgs = true; TemplateArgsPtr.release(); } // C++ [temp.explicit]p1: // A [...] function [...] can be explicitly instantiated from its template. // A member function [...] of a class template can be explicitly // instantiated from the member definition associated with its class // template. UnresolvedSet<8> Matches; for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); P != PEnd; ++P) { NamedDecl *Prev = *P; if (!HasExplicitTemplateArgs) { if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { if (Context.hasSameUnqualifiedType(Method->getType(), R)) { Matches.clear(); Matches.addDecl(Method, P.getAccess()); if (Method->getTemplateSpecializationKind() == TSK_Undeclared) break; } } } FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); if (!FunTmpl) continue; TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); FunctionDecl *Specialization = 0; if (TemplateDeductionResult TDK = DeduceTemplateArguments(FunTmpl, (HasExplicitTemplateArgs ? &TemplateArgs : 0), R, Specialization, Info)) { // FIXME: Keep track of almost-matches? (void)TDK; continue; } Matches.addDecl(Specialization, P.getAccess()); } // Find the most specialized function template specialization. UnresolvedSetIterator Result = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, D.getIdentifierLoc(), PDiag(diag::err_explicit_instantiation_not_known) << Name, PDiag(diag::err_explicit_instantiation_ambiguous) << Name, PDiag(diag::note_explicit_instantiation_candidate)); if (Result == Matches.end()) return true; // Ignore access control bits, we don't need them for redeclaration checking. FunctionDecl *Specialization = cast<FunctionDecl>(*Result); if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_member_function_not_instantiated) << Specialization << (Specialization->getTemplateSpecializationKind() == TSK_ExplicitSpecialization); Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); return true; } FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); if (!PrevDecl && Specialization->isThisDeclarationADefinition()) PrevDecl = Specialization; if (PrevDecl) { bool HasNoEffect = false; if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, PrevDecl, PrevDecl->getTemplateSpecializationKind(), PrevDecl->getPointOfInstantiation(), HasNoEffect)) return true; // FIXME: We may still want to build some representation of this // explicit specialization. if (HasNoEffect) return (Decl*) 0; } Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); if (TSK == TSK_ExplicitInstantiationDefinition) InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization); // C++0x [temp.explicit]p2: // If the explicit instantiation is for a member function, a member class // or a static data member of a class template specialization, the name of // the class template specialization in the qualified-id for the member // name shall be a simple-template-id. // // C++98 has the same restriction, just worded differently. FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && D.getCXXScopeSpec().isSet() && !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) Diag(D.getIdentifierLoc(), diag::ext_explicit_instantiation_without_qualified_id) << Specialization << D.getCXXScopeSpec().getRange(); CheckExplicitInstantiationScope(*this, FunTmpl? (NamedDecl *)FunTmpl : Specialization->getInstantiatedFromMemberFunction(), D.getIdentifierLoc(), D.getCXXScopeSpec().isSet()); // FIXME: Create some kind of ExplicitInstantiationDecl here. return (Decl*) 0; } TypeResult Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, const CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation TagLoc, SourceLocation NameLoc) { // This has to hold, because SS is expected to be defined. assert(Name && "Expected a name in a dependent tag"); NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); if (!NNS) return true; TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); if (TUK == TUK_Declaration || TUK == TUK_Definition) { Diag(NameLoc, diag::err_dependent_tag_decl) << (TUK == TUK_Definition) << Kind << SS.getRange(); return true; } ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); return ParsedType::make(Context.getDependentNameType(Kwd, NNS, Name)); } TypeResult Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, const CXXScopeSpec &SS, const IdentifierInfo &II, SourceLocation IdLoc) { NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); if (!NNS) return true; if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && !getLangOptions().CPlusPlus0x) Diag(TypenameLoc, diag::ext_typename_outside_of_template) << FixItHint::CreateRemoval(TypenameLoc); QualType T = CheckTypenameType(ETK_Typename, NNS, II, TypenameLoc, SS.getRange(), IdLoc); if (T.isNull()) return true; TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); if (isa<DependentNameType>(T)) { DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); TL.setKeywordLoc(TypenameLoc); TL.setQualifierRange(SS.getRange()); TL.setNameLoc(IdLoc); } else { ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); TL.setKeywordLoc(TypenameLoc); TL.setQualifierRange(SS.getRange()); cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); } return CreateParsedType(T, TSI); } TypeResult Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, const CXXScopeSpec &SS, SourceLocation TemplateLoc, ParsedType Ty) { if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && !getLangOptions().CPlusPlus0x) Diag(TypenameLoc, diag::ext_typename_outside_of_template) << FixItHint::CreateRemoval(TypenameLoc); TypeSourceInfo *InnerTSI = 0; QualType T = GetTypeFromParser(Ty, &InnerTSI); assert(isa<TemplateSpecializationType>(T) && "Expected a template specialization type"); if (computeDeclContext(SS, false)) { // If we can compute a declaration context, then the "typename" // keyword was superfluous. Just build an ElaboratedType to keep // track of the nested-name-specifier. // Push the inner type, preserving its source locations if possible. TypeLocBuilder Builder; if (InnerTSI) Builder.pushFullCopy(InnerTSI->getTypeLoc()); else Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc); /* Note: NNS already embedded in template specialization type T. */ T = Context.getElaboratedType(ETK_Typename, /*NNS=*/0, T); ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); TL.setKeywordLoc(TypenameLoc); TL.setQualifierRange(SS.getRange()); TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); return CreateParsedType(T, TSI); } // TODO: it's really silly that we make a template specialization // type earlier only to drop it again here. TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T); DependentTemplateName *DTN = TST->getTemplateName().getAsDependentTemplateName(); assert(DTN && "dependent template has non-dependent name?"); assert(DTN->getQualifier() == static_cast<NestedNameSpecifier*>(SS.getScopeRep())); T = Context.getDependentTemplateSpecializationType(ETK_Typename, DTN->getQualifier(), DTN->getIdentifier(), TST->getNumArgs(), TST->getArgs()); TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); DependentTemplateSpecializationTypeLoc TL = cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc()); if (InnerTSI) { TemplateSpecializationTypeLoc TSTL = cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc()); TL.setLAngleLoc(TSTL.getLAngleLoc()); TL.setRAngleLoc(TSTL.getRAngleLoc()); for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I) TL.setArgLocInfo(I, TSTL.getArgLocInfo(I)); } else { TL.initializeLocal(SourceLocation()); } TL.setKeywordLoc(TypenameLoc); TL.setQualifierRange(SS.getRange()); return CreateParsedType(T, TSI); } /// \brief Build the type that describes a C++ typename specifier, /// e.g., "typename T::type". QualType Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS, const IdentifierInfo &II, SourceLocation KeywordLoc, SourceRange NNSRange, SourceLocation IILoc) { CXXScopeSpec SS; SS.setScopeRep(NNS); SS.setRange(NNSRange); DeclContext *Ctx = computeDeclContext(SS); if (!Ctx) { // If the nested-name-specifier is dependent and couldn't be // resolved to a type, build a typename type. assert(NNS->isDependent()); return Context.getDependentNameType(Keyword, NNS, &II); } // If the nested-name-specifier refers to the current instantiation, // the "typename" keyword itself is superfluous. In C++03, the // program is actually ill-formed. However, DR 382 (in C++0x CD1) // allows such extraneous "typename" keywords, and we retroactively // apply this DR to C++03 code with only a warning. In any case we continue. if (RequireCompleteDeclContext(SS, Ctx)) return QualType(); DeclarationName Name(&II); LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); LookupQualifiedName(Result, Ctx); unsigned DiagID = 0; Decl *Referenced = 0; switch (Result.getResultKind()) { case LookupResult::NotFound: DiagID = diag::err_typename_nested_not_found; break; case LookupResult::NotFoundInCurrentInstantiation: // Okay, it's a member of an unknown instantiation. return Context.getDependentNameType(Keyword, NNS, &II); case LookupResult::Found: if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { // We found a type. Build an ElaboratedType, since the // typename-specifier was just sugar. return Context.getElaboratedType(ETK_Typename, NNS, Context.getTypeDeclType(Type)); } DiagID = diag::err_typename_nested_not_type; Referenced = Result.getFoundDecl(); break; case LookupResult::FoundUnresolvedValue: llvm_unreachable("unresolved using decl in non-dependent context"); return QualType(); case LookupResult::FoundOverloaded: DiagID = diag::err_typename_nested_not_type; Referenced = *Result.begin(); break; case LookupResult::Ambiguous: return QualType(); } // If we get here, it's because name lookup did not find a // type. Emit an appropriate diagnostic and return an error. SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(), IILoc); Diag(IILoc, DiagID) << FullRange << Name << Ctx; if (Referenced) Diag(Referenced->getLocation(), diag::note_typename_refers_here) << Name; return QualType(); } namespace { // See Sema::RebuildTypeInCurrentInstantiation class CurrentInstantiationRebuilder : public TreeTransform<CurrentInstantiationRebuilder> { SourceLocation Loc; DeclarationName Entity; public: typedef TreeTransform<CurrentInstantiationRebuilder> inherited; CurrentInstantiationRebuilder(Sema &SemaRef, SourceLocation Loc, DeclarationName Entity) : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), Loc(Loc), Entity(Entity) { } /// \brief Determine whether the given type \p T has already been /// transformed. /// /// For the purposes of type reconstruction, a type has already been /// transformed if it is NULL or if it is not dependent. bool AlreadyTransformed(QualType T) { return T.isNull() || !T->isDependentType(); } /// \brief Returns the location of the entity whose type is being /// rebuilt. SourceLocation getBaseLocation() { return Loc; } /// \brief Returns the name of the entity whose type is being rebuilt. DeclarationName getBaseEntity() { return Entity; } /// \brief Sets the "base" location and entity when that /// information is known based on another transformation. void setBase(SourceLocation Loc, DeclarationName Entity) { this->Loc = Loc; this->Entity = Entity; } }; } /// \brief Rebuilds a type within the context of the current instantiation. /// /// The type \p T is part of the type of an out-of-line member definition of /// a class template (or class template partial specialization) that was parsed /// and constructed before we entered the scope of the class template (or /// partial specialization thereof). This routine will rebuild that type now /// that we have entered the declarator's scope, which may produce different /// canonical types, e.g., /// /// \code /// template<typename T> /// struct X { /// typedef T* pointer; /// pointer data(); /// }; /// /// template<typename T> /// typename X<T>::pointer X<T>::data() { ... } /// \endcode /// /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, /// since we do not know that we can look into X<T> when we parsed the type. /// This function will rebuild the type, performing the lookup of "pointer" /// in X<T> and returning an ElaboratedType whose canonical type is the same /// as the canonical type of T*, allowing the return types of the out-of-line /// definition and the declaration to match. TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, SourceLocation Loc, DeclarationName Name) { if (!T || !T->getType()->isDependentType()) return T; CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); return Rebuilder.TransformType(T); } ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) { CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(), DeclarationName()); return Rebuilder.TransformExpr(E); } bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { if (SS.isInvalid()) return true; NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), DeclarationName()); NestedNameSpecifier *Rebuilt = Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange()); if (!Rebuilt) return true; SS.setScopeRep(Rebuilt); return false; } /// \brief Produces a formatted string that describes the binding of /// template parameters to template arguments. std::string Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, const TemplateArgumentList &Args) { // FIXME: For variadic templates, we'll need to get the structured list. return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), Args.flat_size()); } std::string Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, const TemplateArgument *Args, unsigned NumArgs) { std::string Result; if (!Params || Params->size() == 0 || NumArgs == 0) return Result; for (unsigned I = 0, N = Params->size(); I != N; ++I) { if (I >= NumArgs) break; if (I == 0) Result += "[with "; else Result += ", "; if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { Result += Id->getName(); } else { Result += '$'; Result += llvm::utostr(I); } Result += " = "; switch (Args[I].getKind()) { case TemplateArgument::Null: Result += "<no value>"; break; case TemplateArgument::Type: { std::string TypeStr; Args[I].getAsType().getAsStringInternal(TypeStr, Context.PrintingPolicy); Result += TypeStr; break; } case TemplateArgument::Declaration: { bool Unnamed = true; if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { if (ND->getDeclName()) { Unnamed = false; Result += ND->getNameAsString(); } } if (Unnamed) { Result += "<anonymous>"; } break; } case TemplateArgument::Template: { std::string Str; llvm::raw_string_ostream OS(Str); Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); Result += OS.str(); break; } case TemplateArgument::Integral: { Result += Args[I].getAsIntegral()->toString(10); break; } case TemplateArgument::Expression: { // FIXME: This is non-optimal, since we're regurgitating the // expression we were given. std::string Str; { llvm::raw_string_ostream OS(Str); Args[I].getAsExpr()->printPretty(OS, Context, 0, Context.PrintingPolicy); } Result += Str; break; } case TemplateArgument::Pack: // FIXME: Format template argument packs Result += "<template argument pack>"; break; } } Result += ']'; return Result; }